The interpretation timeline
Romans 12:2 Douay-Rheims

And be not conformed to this world; but be reformed in the newness of your mind, that you may prove what is the good, and the acceptable, and the perfect will of God.

A.D. 215 – 1871 11 witnesses

Patristic

before A.D. 750
215
A.D.
c. A.D. 150–215
“And akin to love is hospitality, being a congenial an devoted to the treatment of strangers. And those are strangers, to whom the things of the world are strange. For we regard as worldly those, who hope in the earth and carnal lusts. "Be not conformed," says the apostle, "to this world: but be ye transformed in the renewal of the mind, that ye may prove what is that good, and acceptable, and perfect, will of God."”
Source
date
unknown
c. A.D. 380
“We therefore, who have been vouchsafed the favour of being the witnesses of His appearance, together with James the brother of our Lord, and the other seventy-two disciples, and his seven deacons, have heard from the mouth of our Lord Jesus Christ, and by exact knowledge declare "what is the will of God, that good, and acceptable, and perfect will" which is made known to us by Jesus; that none should perish, but that all men with one accord should believe in Him, and send unanimously praise to Him, and thereby live for ever.”
Source
395
A.D.
Gregory of Nyssa Patristic
c. A.D. 335–395
“The perfect will of God is that the soul be changed by reverence, having been brought to the full flower of its beauty by the grace of the Spirit, which attends to the sufferings of the person who undergoes the change.”
407
A.D.
John Chrysostom Patristic
A.D. 347–407
“"And be not fashioned after this world; but be ye transformed by the renewing of your mind." For the fashion of this world is grovelling and worthless, and but for a time, neither bath ought of loftiness, or lastingness, or straightforwardness, but is wholly perverted. If then thou wouldest walk upright, figure not thyself after the fashion of this life present. For in it there is nought abiding or stable. And this is why he calls it a fashion; and so in another passage, "the fashion of this world passeth away." For it hath no durability or fixedness, but all in it is but for a season; and so he calls it this age, hereby to indicate its liableness to misfortune, and by the word fashion its unsubstantialness. For speak of riches, or of glory, or beauty of person, or of luxury, or of whatever other of its seemingly great things you will, it is a fashion only, not reality, a show and a mask, not any abiding substance. But "be not thou fashioned after this, but be transformed," he says, "by the renewing of your mind." He says not change the fashion, but "be transformed", to show that the world's ways are a fashion, but virtue's not a fashion, but a kind of real form, with a natural beauty of its own, lacking not the trickeries and fashions of outward things, which no sooner appear than they go to nought. For all these things, even before they come to light, are dissolving. If then thou throwest the fashion aside, thou wilt speedily come to the form. For nothing is more strengthless than vice, nothing so easily wears old. Then since it is likely that being men they would sin every day, he consoles his hearer by saying, "renew thyself" from day to day. This is what we do with houses, we keep constantly repairing them as they wear old, and so do thou unto thyself. Hast thou sinned to-day? hast thou made thy soul old? despair not, despond not, but renew it by repentance, and tears, and confession, and by doing of good things. And never fail of doing this. And how are we to do this? "That ye may prove what is that good, and acceptable, and perfect will of God." Either he means by this, be renewed, that ye may learn what is more expedient for you, and what the will of God. Or rather, that ye can get so renewed if ye learn the things expedient, and what God may will. For if thou see this, and know how to distinguish the nature of things, thou art in possession of the whole way of virtue. And who, it may be said, is ignorant of what is expedient, and what is the will of God? They that are flurried with the things of this world, they that deem riches an enviable thing, they that make light of poverty, they that follow after power, they that are gaping after outward glory, they that think themselves great men when they raise fine houses, and buy costly sepulchres, and keep herds of slaves, and carry a great swarm of eunuchs about with them; these know not what is expedient for them, or what the will of God is. For both of these are but one thing. For God willeth what things are expedient for us, and what God willeth, that is also expedient for us. What then are the things which God willeth? to live in poverty, in lowliness of mind, in contempt of glory; in continency, not in self-indulgence; in tribulation, not in ease; in sorrow, not in dissipation and laughter; in all the other points whereon He hath given us laws. But the generality do even think these things of ill omen; so far are they from thinking them expedient, and the will of God. This then is why they never can come near even to the labors for virtue's sake. For they that do not know so much even as what virtue may be, but reverence vice in its place, and take unto their bed the harlot instead of the modest wife, how are they to be able to stand aloof from the present world? Wherefore we ought above all to have a correct estimate of things, and even if we do not follow after virtue, to praise virtue, and even if we do not avoid vice, to stigmatize vice, that so far we may have our judgments uncorrupted. For so as we advance on our road, we shall be able to lay hold on the realities. This then is why he also bids you be renewed, "that ye may prove what is the will of God." But here he seems to me to be attacking the Jews too, who cling to the Law. For the old dispensation was a will of God, yet not the ultimate purpose, but allowed owing to their feebleness. But that which is a perfect one, and well-pleasing, is the new conversation. So too when he called it "a reasonable service," it was to set it in contrast with that other that he gave it such a name.”
Source
430
A.D.
Augustine of Hippo Patristic
A.D. 354–430
“Those who are moved … to turn again to the Lord out of that state of deformity wherein worldly desires conformed them to this world must receive from the Lord their reformation.”

Scholastic

c. 1100 – 1500
1273
A.D.
Thomas Aquinas Catholic
1225–1274
“After the Apostle showed the necessity of the virtues and the origin of grace, here he teaches the use of grace, which pertains to moral instruction. And concerning this he does two things. First he sets down moral teaching in general; second he descends specially to certain particulars pertaining to those to whom he writes, around the middle of chapter XV, where he says, but I myself am persuaded, and so on. Concerning the first he does two things. First he teaches the use of grace as to this, that man be made perfect; second as to this, that the perfect man should bear with the imperfect one, in chapter XIV, where he says, now him who is weak, and so on. Concerning the first he does three things. First he leads on to perfection of life as to the holiness which man keeps toward God; second as to the justice which one shows to one's neighbor, in chapter XIII, where he says, let every soul, etc.; third as to the purity which man preserves in himself, near the end of chapter XIII, where he says, and knowing this, and so on. Concerning the first he does two things. First he admonishes that man show himself holy to God; second he teaches how one ought to use the gifts of God's grace, by which one is sanctified, where he says, for I say, through the grace, and so on. Concerning the first he does two things. First he teaches how one ought to show oneself to God as to the body; second as to the soul, where he says, and be not conformed, and so on. Concerning the first he does two things. First he induces observance of the things that are taught: and this in two ways. In one way indeed on his own part, when he says, I beseech you therefore, brethren, as if he were to say: it has been said that the judgments of God are incomprehensible, and his ways unsearchable, and therefore I beseech you, brethren, namely that you observe the things that shall be said. Now he makes use of beseeching for three reasons. First indeed to show his humility. Proverbs XVIII, 23: the poor man speaketh with supplications, namely one who does not trust in his own abundance, and therefore tries to lead men to the good not from what is his own, but from what is God's. For to beseech (obsecrare) is to call to witness by sacred things (ob sacra contestari). Second, that he might move them more by love in asking, than by fear, in commanding with authority. Whence it is said to Philemon 8f.: having much confidence in Christ Jesus to command thee that which is to the purpose, for charity's sake I rather beseech. Galatians, last chapter: you who are spiritual, instruct such a one in the spirit of gentleness. Third, on account of the reverence due to the Romans, to whom he was writing. I Timothy V, 1: rebuke not an elder, but beseech him as a father. In another way he leads them on on God's part, when he says, by the mercy of God, namely by which you have been saved. Titus II, 5: according to his mercy he saved us. And therefore from consideration of the divine mercy we ought to do what we are admonished to do. Matthew XVIII, 33: shouldst not thou also have had compassion on thy fellow servant, even as I had compassion on thee? Or it can be said, by the mercy of God, that is, by the authority of the apostolate mercifully entrusted to me. I Corinthians VII, 25: I have obtained mercy from the Lord, to be faithful. Second he sets down the admonition, when he says, that you present your bodies, and so on. Concerning which it must be known that, as Augustine says in Book X of the City of God, the visible sacrifice, which is offered outwardly to God, is a sign of the invisible sacrifice, by which one presents oneself and one's own things in obedience to God. Now man has a threefold good. First indeed the good of the soul, which he presents to God through the humility of devotion and contrition, according to that word of Psalm 50, 19: a sacrifice to God is an afflicted spirit. Second, man has exterior goods, which he presents to God through the giving of alms. Whence it is said in Hebrews, last chapter: do not forget to do good and to share, for by such sacrifices God is won over. Third, man has the good of his own body: and as to this he says, that you present, namely to God, your bodies, as a certain spiritual sacrificial victim. Now an animal immolated to God used to be called a "hostia" (sacrificial victim), either because it was offered for victory over enemies (hostes), or for security from enemies, or because it was immolated at the door (ostium) of the tabernacle. Now man presents his body to God as a sacrificial victim in three ways. In one way indeed, when someone exposes his body to suffering and death for God's sake, as is said of Christ, Ephesians V, 2: he delivered himself up for us, an oblation and a sacrifice to God. And the Apostle says of himself, Philippians II, 17: if I be sacrificed upon the sacrifice and service of your faith, I rejoice. Second, by this, that man macerates his body with fastings and watchings in order to serve God, according to that word of I Corinthians IX, 27: I chastise my body, and bring it into subjection. Third, by this, that man presents his body for carrying out works of justice and of divine worship. Above, VI, 19: present your members to serve justice, unto sanctification. Now it must be considered that the sacrificial victim which was immolated to God had four properties. For first, the offering itself had to be whole and uncorrupted. Whence it is said, Malachi I, v. 14: cursed is the deceitful man, who hath in his flock a male, and making a vow, offereth in sacrifice that which is feeble to the Lord. And on account of this he says, living, namely that the sacrificial victim of our body which we offer to God should be living through faith formed by charity. Galatians II, 20: that which I now live in the flesh, I live in the faith of the Son of God. Now it must be noted that the natural sacrificial victim which had previously been alive, used to be killed, in order to be immolated, to show that death still reigned in man while sin reigned, as was said above at V, 12ff. But this spiritual sacrificial victim always lives and progresses in life, according to that word of John X, 10: I am come that they may have life, and have it more abundantly, because sin has now been taken away through Christ: unless we should say that the sacrificial victim of our body indeed lives to God through the justice of faith, but is put to death as to the concupiscences of the flesh. Colossians III, 5: mortify your members which are upon the earth. Second, the sacrificial victim offered to God was sanctified in the very immolation. Whence it is said, Leviticus XXII, 3: any man of your race, that approacheth to those things that are consecrated, and which the children of Israel have offered to the Lord, in whom there is uncleanness, shall perish before the Lord. And therefore he adds, holy, namely through the devotion by which our body is bound over to the service of God. Leviticus XX, 7: be ye sanctified and be ye holy, for I am the Lord your God, who is holy. Now holiness is properly spoken of with respect to God, inasmuch namely as man keeps those things that are just, as regards God. Third, as to the very consumption of the sacrifice, it was called a sacrifice sweet and acceptable to the Lord, according to that word of Leviticus I, v. 9: the priest shall burn all the things offered upon the altar for a holocaust, and for a most sweet odor to the Lord. Whence here he says, pleasing to God, namely through rectitude of intention. Psalm 55, 13: that I may please in the sight of God, in the light of the living. Fourth, in the very preparation of the sacrifice salt was added. Whence Leviticus II, 13: whatsoever sacrifice thou offerest, thou shalt season it with salt. And Mark IX, 48 it is said: every victim shall be salted with salt. Now salt signifies the discernment of wisdom. Whence it is said, Colossians, last chapter: walk with wisdom towards them that are without, let your speech be always in grace seasoned with salt. Whence also here follows, your reasonable service, namely that with discernment you present your bodies to God as a sacrificial victim, whether through martyrdom or through abstinence or through whatever work of justice. I Corinthians XIV, 40: let all things be done decently, and according to order among you. And Psalm 98, 4: the king's honor loveth judgment. The just man is related differently to interior acts, by which he does service to God, than to exterior ones. For the good of man and his justice consists principally in interior acts, namely those by which man believes, hopes, and loves. Whence it is said, Luke XVII, 21: the kingdom of God is within you. But it does not consist principally in exterior acts. Below, XIV, v. 17: the kingdom of God is not meat and drink. Whence the interior acts are related after the manner of an end, which is sought for its own sake: but the exterior acts, by which bodies are presented to God, are related as those things which are for the end. Now in that which is sought as an end no measure is applied, but the greater it is, the better it is. But in that which is sought for the sake of an end, a measure is applied according to proportion to the end, just as a physician produces health as much as he can, but he does not give medicine as much as he can, but as much as he sees to be expedient for attaining health. And likewise man ought to apply no measure in faith, and hope, and in charity, but the more he believes, hopes, and loves, the better it is; on account of which it is said, Deuteronomy IV, 5: thou shalt love the Lord thy God, and so on. But in exterior acts a measure of discernment must be applied by comparison to charity. Whence Jerome says: does not a rational man lose his dignity, who prefers fasting or vigils to soundness of sense, so that on account of the chanting of psalms and offices, he incurs a mark of madness or of sadness? Then when he says, and be not conformed, etc., he shows how man ought to present himself to God as to the soul. And first he forbids conformity to the world, when he says, and be not conformed to this world, that is, to the things which pass away in time. For the present age (saeculum) is a certain measure of the things that pass away in time. Now man is conformed to temporal things through affection, by clinging to them with love. Hosea IX, v. 10: they became abominable, as those things which they loved. James I, 27: religion clean and undefiled before God and the Father is this: to keep oneself unspotted from this world. He is also conformed to this world who imitates the life of those who live worldly lives. Ephesians IV, 17: I testify in the Lord, that henceforward you walk not as also the Gentiles walk. Second he commands an interior reformation of the mind, when he says, but be reformed in the newness of your understanding. Now the "sense" (sensus) of man is here called reason, according as through it man judges concerning things to be done. Now man had this sense whole and vigorous in his creation, whence it is said, Ecclesiasticus XVII, 6: understanding filled their hearts, and showed them good and evil. But through sin this sense has been corrupted, and, as it were, made old, Baruch III, 11: thou art grown old in a strange land, and consequently it has lost its beauty and comeliness. Lamentations I, 6: from the daughter of Sion all her beauty is departed. The Apostle therefore admonishes that we be reformed, that is, that we take up again the form and comeliness of mind, which our mind had, which indeed comes about through the grace of the Holy Spirit, in participating in which man ought to have zeal, namely in such a way that those who have not yet received it may receive it, and those who have received it may progress in it. Ephesians IV, 23: be renewed in the spirit of your mind. Psalm 102, 5: thy youth shall be renewed like the eagle's. Or otherwise, be renewed, namely in exterior acts, in the newness of your understanding, that is, according to the newness of grace, which you have received in your mind. Third he assigns the reason for the aforesaid admonition, when he says, that you may prove what is the will. Concerning which it must be considered that, just as a man who has a corrupted taste does not have a right judgment concerning flavors, but sometimes abominates the things that are sweet, and desires the things that are abominable, whereas he who has a sound taste has a right judgment concerning flavors; so the man who has a corrupted affection, as it were conformed to worldly things, does not have a right judgment concerning the good; but he who has a right and sound affection, his sense renewed through grace, has a right judgment concerning the good. Therefore he said: be not conformed to this world, but be reformed in the newness of your understanding, that you may prove, that is, that you may know by experience — Psalm 33, 9: taste and see that the Lord is sweet —, what is the will of God, by which namely he wills you to be saved — I Thessalonians IV, 3: this is the will of God, your sanctification —, good, that is, he wills that we will the honest good, and to this he leads us by his precepts — Micah VI, 8: I will show thee, O man, what is good, and what the Lord requireth of thee —, and well-pleasing, inasmuch namely as, to one well-disposed, that which God wills us to will is delightful. Psalm 18, v. 9: the justices of the Lord are right, rejoicing hearts. And not only useful for attaining the end, but also perfect, as it were joining us to the end. Matthew V, 48: be ye perfect, as also your heavenly Father is perfect. Genesis XVII, 1: walk before me, and be perfect. Those, therefore, who are not conformed to this world, but are reformed in the newness of their sense, experience the will of God to be such. But those who remain in oldness, conformed to the world, judge the will of God not to be good, but heavy and useless. Ecclesiasticus VI, 21: how exceeding harsh is wisdom to unlearned men. Then, when he says, for I say, through the grace, etc., he teaches how man ought to use the gifts of God. And first he teaches this as to the gifts which are not common to all, such as the graces freely given (gratiae gratis datae); second, as to the gift of charity, which is common to all, where he says, let love be without dissimulation, and so on. Concerning the first he does two things. First he teaches in general how man ought to use the graces freely given; second he carries this out part by part, where he says, but having different gifts. Concerning the first he does two things. First he sets forth the instruction; second he assigns the reason, where he says, for as in one body, and so on. Concerning the first he does three things. First he excludes excess, saying: I have admonished that you be reformed in the newness of your understanding, which indeed you ought to do with moderation; for I say, that is, I command, through the grace, of the apostolate and by apostolic authority, that is given to me. Galatians II, 9: when they had known the grace that was given to me among the Gentiles. Ephesians III, 8: to me, the least of all the saints, is given this grace, etc., to all that are among you, because this is useful to all. I Corinthians VII, 7: I would that all men were even as myself. This, I say, I command: not to be more wise than it behooveth to be wise, that is, let no one, trusting in his own understanding or wisdom, presume beyond his measure. Ecclesiastes VII, 17: be not more wise than is necessary. Psalm 130, 1: neither have I walked in great matters, nor in wonderful things above me. Second he exhorts to that which is the mean, saying, but to be wise unto sobriety, namely I command you that you be wise with measure according to the grace given to you. For sobriety imports measure. And although it is properly said concerning the drinking of wine, it can nevertheless be taken concerning any matter whatsoever, in which man observes due measure. Titus II, v. 12: that we may live soberly, and justly, and godly in this world. Third he teaches according to what the measure of the mean is to be taken, saying, and this, I say, according as God hath divided, that is, distributed, to every one the measure of faith, that is, the measure of his gifts, which is ordered to the building up of faith. I Corinthians XII, 7: to every man is given the manifestation of the spirit unto profit. For God gives gifts of this kind, not the same to all, but distributes different ones to different people, according to that word of I Corinthians XII, 4: there are diversities of graces. Nor does he give equally to all, but to each one according to a fixed measure. Ephesians IV, 7: to every one of us is given grace according to the measure of the giving of Christ. And therefore the Apostle, being wise soberly according to this measure, said, II Corinthians X, 13: but we will not glory beyond our measure, but according to the measure of the rule, which God hath measured to us. Now to Christ alone was the spirit given not by measure, as is said in John III, 34. Now God gives not only the other graces freely given with measure, but also faith itself, which works through love. Whence Luke XVII, v. 5 the disciples said to Christ: Lord, increase our faith.”

Post-Reformation

c. 1650 – 1900
1771
A.D.
John Gill Reformed
1697–1771
“And be not conformed to this world,.... By this world is meant, either the Mosaic dispensation, and Jewish church state, so called in opposition to , "the world to come", the Gospel dispensation; in which there were a worldly sanctuary, and the rites and ceremonies of which are styled the rudiments and elements of the world; to which believers in the present state are by no means to conform, there being sacrifices and ordinances of another nature, it is the will of God they should observe and attend unto: or else the men of the world are designed, carnal and unregenerate men, among whom they formerly had their conversation, from among whom they were chosen, called, and separated, and who lie and live in wickedness, and therefore should not be conformed unto them: which is to be understood, not in a civil sense of conformity to them in garb and apparel, provided that pride and luxury are guarded against, and decency and sobriety observed, and the different abilities of persons and stations in life are attended to; or to any other civil usages and customs which are not contrary to natural and revealed religion; but of a conformity in a moral sense to the evil manners of men, to walk vainly, as other Gentiles do, to go into the same excess of riot with them; for this is contrary both to the principle and doctrine of grace, which teach men to deny ungodliness and worldly lusts: and of a compliance with the men of the world in a religious sense, by joining with them in acts of idolatry, superstition, and will worship, and in anything that is contrary to the order, ordinances, and truths of the Gospel. But be ye transformed by the renewing of your mind; which regards not the first work of conversion and renovation; for in this sense these persons were transformed, metamorphosed, changed, and renewed already; but the after progress and carrying on the work of renovation, the renewing of them day by day in the spirit of their minds; see Eph 4:23; which believers should be desirous of, and pray for, and make use of those means which the Spirit of God owns for this purpose, attending to the spiritual exercises of religion, as reading, meditation, prayer, conference, the ministration of the word and ordinances, which is the reverse of conformity to the world: and the end to be attained hereby is, that ye may prove what is that good, and acceptable, and perfect will of God; by which is meant not the secret will of God, which cannot be searched into, proved, and known, till time and facts discover it: but the revealed will of God, both in the law, as in the hands of Christ, which contains nothing but what is good; and which when done in faith, from a principle of love, and to the glory of God, is acceptable through Christ; and is perfect as a law of liberty, and rule of walk and conversation; and which is to be proved and approved of by all the saints, who delight in it after the inward man: and also that which is contained in the Gospel; as that all that the Father had given to Christ should be redeemed by him, that these should be sanctified, and persevere to the end, and be glorified; all which is the good will of God, an acceptable saying to sensible sinners, and such a scheme of salvation as is perfect and complete, and needs nothing to be added to it; and is, by such who are daily renewed in the spirit of their minds, more and more proved, tried, discerned, and approved of, even by all such who have their spiritual senses exercised to discern things that differ.”
Source
1832
A.D.
Adam Clarke Methodist
1762–1832
“And be not conformed to this world - By this world, αιωνι τουτῳ, may be understood that present state of things both among the Jews and Gentiles; the customs and fashions of the people who then lived, the Gentiles particularly, who had neither the power nor the form of godliness; though some think that the Jewish economy, frequently termed עולם הזה olam hazzeh, this world, this peculiar state of things, is alone intended. And the apostle warns them against reviving usages that Christ had abolished: this exhortation still continues in full force. The world that now is - This present state of things, is as much opposed to the spirit of genuine Christianity as the world then was. Pride, luxury, vanity, extravagance in dress, and riotous living, prevail now, as they did then, and are as unworthy of a Christian's pursuit as they are injurious to his soul, and hateful in the sight of God. Be ye transformed - Μεταμορφουσθε, Be ye metamorphosed, transfigured, appear as new persons, and with new habits, as God has given you a new form of worship, so that ye serve in the newness of the spirit, and not in the oldness of the letter. The word implies a radical, thorough, and universal change, both outward and inward. Seneca, Epis. vi, shows us the force of this word when used in a moral sense. Sentio, says he, non Emendari me tantum, sed Transfigurari; "I perceive myself not to be amended merely, but to be transformed:" i. e entirely renewed. By the renewing of your mind - Let the inward change produce the outward. Where the spirit, the temper, and disposition of the mind, Eph 4:23, are not renewed, an outward change is of but little worth, and but of short standing. That ye may prove - Εις το δοκιμαζειν, That ye may have practical proof and experimental knowledge of, the will of God - of his purpose and determination, which is good in itself; infinitely so. Acceptable, ευαρεστον, well pleasing to and well received by every mind that is renewed and transformed. And perfect - Τελειον, Finished and complete: when the mind is renewed, and the whole life changed, then the will of God is perfectly fulfilled; for this is its grand design in reference to every human being. These words are supposed by Schoettgen to refer entirely to the Jewish law. The Christians were to renounce this world - the Jewish state of things; to be transformed, by having their minds enlightened in the pure and simple Christian worship, that they might prove the grand characteristic difference between the two covenants: the latter being good in opposition to the statutes which were not good, Eze 20:25; acceptable, in opposition to those sacrifices and offerings which God would not accept, as it is written, Psa 40:6-8; and perfect, in opposition to that system which was imperfect, and which made nothing perfect, and was only the shadow of good things to come. There are both ingenuity and probability in this view of the subject.”
Source
1849
A.D.
1774–1849
“Take care, lest you imitate the practices of worldlings. Let your heart, your ambition, carry you to heaven: ever despise those things which the world admires, that every one may see by your actions that you are not of the society of worldlings, and have neither regard nor friendship for them. (Calmet) — Transform yourselves into new men, by the renewal of your mind, that you may discern on all occasions, what is most perfect, most pleasing and acceptable to God. (Bible de Vence)”
Source
1863
A.D.
1796–1863
“These epithets contain a climax. The will of God is good in itself. We should obey the Divine commandments, and aspire after perfection, doing always what may be more agreeable to God. Eph. v. 17; 1 Thess. iv. 3. St. Chry- sostom thinks that the apostle refers to the Christian code, as contrasted with the Jewish.”
1871
A.D.
1871
“And be ye not conformed to this world--Compare Eph 2:2; Gal 1:4, Greek. but be ye transformed--or, "transfigured" (as in Mat 17:2; and Co2 3:18, Greek). by the renewing of your mind--not by a mere outward disconformity to the ungodly world, many of whose actions in themselves may be virtuous and praiseworthy; but by such an inward spiritual transformation as makes the whole life new--new in its motives and ends, even where the actions differ in nothing from those of the world--new, considered as a whole, and in such a sense as to be wholly unattainable save through the constraining power of the love of Christ. that ye may prove--that is, experimentally. (On the word "experience" see on Rom 5:4, and compare Th1 5:10, where the sentiment is the same). what is that--"the" good and acceptable--"well-pleasing" and perfect, will of God--We prefer this rendering (with CALVIN) to that which many able critics [THOLUCK, MEYER, DE WETTE, FRITZSCHE, PHILIPPI, ALFORD, HODGE] adopt--"that ye may prove," or "discern the will of God, [even] what is good, and acceptable, and perfect." God's will is "good," as it demands only what is essentially and unchangeably good (Rom 7:10); it is "well pleasing," in contrast with all that is arbitrary, as demanding only what God has eternal complacency in (compare Mic 6:8, with Jer 9:24); and it is "perfect," as it required nothing else than the perfection of God's reasonable creature, who, in proportion as he attains to it, reflects God's own perfection. Such then is the great general duty of the redeemed--SELF-CONSECRATION, in our whole spirit and soul and body to Him who hath called us into the fellowship of His Son Jesus Christ. Next follow specific duties, chiefly social; beginning with Humility, the chiefest of all the graces--but here with special reference to spiritual gifts.”
Source
Modern · 1953 →

The in-app commentary runs from the Fathers to the early-modern record, then stops — that's where the public-domain sources end, not where the reading does. For the modern reading, follow the sources directly.