The interpretation timeline
2 Timothy 1:9 Douay-Rheims

Who hath delivered us and called us by his holy calling, not according to our works, but according to his own purpose and grace, which was given us in Christ Jesus before the times of the world.

A.D. 373 – 1871 7 witnesses

Patristic

before A.D. 750
373
A.D.
c. A.D. 296–373
“Here again allusion is made to the economy according to the flesh. For the grace which came to us from the Savior appeared, as the apostle says, just now, and has come when he sojourned among us. Yet this grace has been prepared even before we came into being.… The God of all then created us by his own Word, and knowing our destinies better than we, God foresaw that even though we were made "good," we should be transgressors of the commandment and be thrust out of paradise for disobedience. Being loving and kind, he prepared beforehand in his own Word, by whom also he created us, the economy of our salvation. Though by the serpent's deceit we fell from him, we would not remain wholly dead, but having in the Word the redemption and salvation which was earlier prepared for us, we might rise again and abide immortal.”
Source
407
A.D.
John Chrysostom Patristic
A.D. 347–407
“"According to the power of God; Who hath saved us, and called us with a holy calling, not according to our works, but according to His own purpose and grace, which was given us in Christ Jesus before the world began." More especially because it was a hard thing to say, "Be partakers of afflictions," he again consoles him. Reckon that thou sustainest these things, not by thine own power, but by the power of God. For it is thy part to choose and to be zealous, but God's to alleviate sufferings and bid them cease. He then shows him the proofs of His power. Consider how thou wast saved, how thou wast called. As he elsewhere says, "According to His power that worketh in us." (Eph. iii. 20) So much was it a greater exercise of power to persuade the world to believe, than to make the Heavens. But how was he "called with a holy calling"? This means, He made them saints, who were sinners and enemies. "And this not of ourselves, it was the gift of God." If then He is mighty in calling us, and good, in that He hath done it of grace and not of debt, we ought not to fear. For He Who, when we should have perished, saved us, though enemies, by grace, will He not much more cooperate with us, when He sees us working? "Not according to our own works," he says, "but according to his own purpose and grace," that is, no one compelling, no one counseling Him, but of His own purpose, from the impulse of His own goodness, He saved us; for this is the meaning of "according to His own purpose." "Which was given us before the world began." That is, it was determined without beginning that these things should be done in Christ Jesus. This is no light consideration, that from the first He willed it. It was not an after-thought. How then is not the Son eternal? for He also willed it from the beginning.”
Source
430
A.D.
Augustine of Hippo Patristic
A.D. 354–430
“Why, then, is it that, in what follows, where they mention what the Pelagians themselves think, they say they confess that "grace also assists the good purpose of every one, but that yet it does not infuse the desire of virtue into a reluctant heart"? They say this as if man of himself, without God's assistance, has a good purpose and a desire of virtue, hence this preceding merit is supposedly worthy of being assisted by the subsequent grace of God. For they think perhaps that the apostle thus said, "For we know that he works all things for good to them that love God, to them who are called according to the purpose," so as to wish the purpose of man to be understood. This purpose is then viewed as a good merit that the mercy of the God who calls might follow. They are ignorant that it is said, "Who are called according to the purpose," so that this may be understood as the purpose of God, not man. Thus those whom he foreknew and predestinated as conformed to the image of his Son, he elected before the foundation of the world.… This then is the purpose of God, in relation to which it is said, "He works together all things for good for those who are called according to his own purpose." Indeed subsequent grace assists man's good purpose, but the purpose itself would not exist if grace did not precede.”
Source

Scholastic

c. 1100 – 1500
1273
A.D.
Thomas Aquinas Catholic
1225–1274
“Above he commended him for gratuitous gifts; here he exhorts him to the use of the gratuitous gifts given to him, especially in the preaching of the Gospel. And first he admonishes him in general to the use of the grace given to him; second he specifies what the use of the grace should be, at the place, "Be not thou ashamed therefore." Likewise, first he sets down the admonition; second, its reason, at the place, "for he hath not given us." He says therefore: the faith unfeigned is in thy mother and grandmother and in thee, for which cause I admonish thee. The grace of God is like a fire which, when it is covered over with ash, does not shine: so grace is covered over in man through torpor, or human fear. Hence Timothy too, having become fainthearted, had grown sluggish about preaching. And therefore he says that thou mayest stir up the grace that is asleep. 1 Thess. 5:19: Extinguish not the spirit. And he adds, which is in thee by the imposition of my hands, namely, by which he had been ordained bishop. In which imposition of hands the grace of the Holy Spirit was given to him. Then, when he says, for... not, the reason for the admonition is set down, and it is taken from the condition of the divine gifts. For he who receives a gift ought to work in accordance with the fittingness of the gift; therefore according to the condition of the divine gifts we ought to serve God. Now there is a twofold spirit, that of this world, and that of God. And the distinction of these is this: for spirit signifies love, because the name "spirit" imports impulsion, and love impels. But love is twofold, namely, of God, and this is through the spirit of God; and love of the world, and this is through the spirit of the world. 1 Cor. 2:12: For we have not received the spirit of this world, etc. But the spirit of the world causes one to love the goods of the world, and to fear temporal evils; and therefore he says, for God hath not given us the spirit of fear, namely, worldly fear, because this God takes away from us. Matt. 10:28: Fear ye not them that kill the body, etc. There is another spirit, the spirit of the fear of the Lord, and it is holy, and this causes God to be feared; but this fear is without punishment and without offense, and this is from God. Matt. 10:28: Fear him who can destroy both soul and body in hell. And he adds, but of power, because through the Holy Spirit we are directed amid evils, and this through power, namely, of fortitude against the adversities of the world. Luke, last chapter: Sit ye in the city till you be endued with power from on high. Likewise we are directed amid goods, because as to affection we are ordered through the love of charity, while one refers all that he loves to God. Hence he says, and of love. 1 John 3:14: He who loveth not, abideth in death. Likewise as to exterior goods; and therefore he says, and of sobriety, that is, of all temperance, by keeping the due mode and measure, namely, that we use the goods of the world temperately. Titus 2:12: That we should live soberly, and justly, and godly in this world. 1 Tim. 3:2: It behooveth a bishop to be blameless, the husband of one wife, sober. Then, when he says, be not, he specifies the use of grace; and first he excludes the things contrary to this use; second he exhorts to the use of grace, at the place, but labor together with. But from his accustomed preaching he could be hindered on account of two things. First, through shame; second, from the punishment of the apostle, which he was suffering on account of the Gospel. And therefore, as to the first, he says, be not therefore, namely, since thou hast the spirit of fortitude, ashamed, etc. For the preaching of Christ, if it be referred to the wisdom of the world, seemed foolish, hence it seemed to have shame. 1 Cor. 1:23: We preach Christ crucified, unto the Jews indeed a stumbling block, and unto the Gentiles foolishness. Rom. 1:16: For I am not ashamed of the Gospel. Luke 9:26: He that shall be ashamed of me and of my words, of him shall the Son of man be ashamed. As to the second, it must be known that if a robber sees someone hanged, he is ashamed to confess himself his companion. So, because the apostle was in chains, Timothy could be ashamed of him; and therefore he says, nor of me his prisoner. Eph. 6:20: For which I am an ambassador in a chain. Ecclus. 4:27: Be not ashamed of thy neighbor in his fall. Then, when he says, but labor together with, he exhorts to the use of grace; and first in general; second he shows with what confidence he should undertake this use, at the place, according to the power. Here he makes manifest what he says, but labor together with, at the place, not according to, etc. He says therefore: be not ashamed, but labor together with, that is, labor along with me. 1 Cor. 3:8: Every man shall receive his own reward. And he says Evangelio, which can be of the ablative case, and thus, in preaching the Gospel; or of the dative case, and thus, to the praise of the Gospel, namely, that it may grow. Wis. 3:15: Glorious is the fruit of good labors, etc. And this with confidence, not one's own, because we are not sufficient to think any thing of ourselves, as of ourselves, etc.; but according to the power of God, that is, having confidence in the power of God. Is. 40:29: Who giveth strength to the weary, and to them that are not, he multiplieth fortitude and strength. This power is made manifest through two things: namely, as to affection, because we are freed from evils; and therefore he says, who hath delivered us. 1 Esdr. 8:31: He delivered us from the hand of the enemy, and of the ambusher by the way. John 8:36: If the son hath made you free. And as to this, that he calls us unto goods. Hence there follows, and calleth us by his holy calling, because he has called us unto sanctification. Rom. 8:30: Whom he predestinated, them he also called. 1 Pet. 2:9: Who hath called us out of darkness into his marvelous light. And he makes manifest certain things which he says, saying, not according to our works; where he shows that we have been freed and called through the power of God, not through human power. And first he shows that the cause of our calling and deliverance is from God; second, the process of the cause, at the place, which was given also; third he commends the giver of the cause, namely, of grace, and its preserver, at the place, who hath destroyed. He says therefore: he called us not through our own power, namely, not through our works, which are the effects of power. Titus 3:5: Not by the works of justice which we have done, but according to his mercy he saved us. Now the cause of human salvation which is from God is twofold. One is eternal, namely, his predestination; the other is temporal, namely, justifying grace. As to the first he says, according to the purpose, that is, predestination, which is the purpose of having mercy. Eph. 1:11: Worketh all things according to the purpose of his will. Rom. 8:28: To them who, according to his purpose, are called to be saints. As to the second he says, and grace. Rom. 3:24: Being justified freely by his grace. Concerning the process of grace, first he shows how grace was prepared; second, how it was bestowed; third, through whom. He shows the first, when he says, which was given to us in Christ Jesus, that is, it was foreseen to be given to us before the times of the world. As the Philosopher says, an age is nothing other than a measure of the duration of certain things; hence different ages are the different lifetimes of men. Hence one age lasts a thousand years, because a man is said to live as long as he is in the memory of men, which does not exceed a thousand years. The times of the world, therefore, are those which measure changeable things, and these began with the world; but predestination is before the world. Eph. 1:4: He chose us in him before the foundation of the world. And he says, in Christ Jesus, because we are not so elected as to be saved by our own merits, but through the grace of Christ; because as he predestined our salvation, so also the mode of our salvation. John 1:17: Grace and truth was made through Jesus Christ. But this predestination was formerly hidden, but now it is made manifest. And how? As the concept of the heart is made manifest through works; hence now, in the effect of the work, he has manifested it to his elect through illumination. He speaks properly; for to manifest is to bring into the light. Job 28:11: He hath brought hidden things into the light. So then it has now been manifested, etc., through the fact that he sent Christ to illumine us. Is. 60:1: Arise, be enlightened, O Jerusalem, for thy light is come. Luke 1:79: To enlighten them that sit in darkness and in the shadow of death. Then, when he says, who hath destroyed, he commends Christ the illuminator; and first his power as to the evils which he took away; second, as to the goods which he conferred. He says therefore that Christ, on account of the fact that he suffered for us, destroyed death, that is, he made satisfaction to God for our sins. 1 Pet. 3:18: Christ died once for our sins, etc. And sin was the cause of our bodily death. Rom. 6:23: For the wages of sin is death; and therefore by destroying sin, he destroyed death. Hos. 13:14: I will be thy death, O death, etc. He also conferred perfect goods: first, to the soul in the present, through the grace of faith. Hab. 2:4: My just man liveth by faith. And it is imperfect in this life, but it will be perfected in glory. John 17:3: This is eternal life, that they may know thee. Second, the immortality of the flesh resulting from the glory of the soul. 1 Cor. 15:53: This corruptible must put on incorruption, etc. John 10:10: I am come that they may have life, namely, now through grace, and may have it more abundantly, namely, through glory in the future; likewise in the same place, 11:26: Whosoever liveth and believeth in me shall not die forever.”

Post-Reformation

c. 1650 – 1900
1771
A.D.
John Gill Reformed
1697–1771
“Who hath saved us, and called us,.... And therefore should not be ashamed of his Gospel, but should readily partake of the afflictions of it, depending on his power to support under them. There is a salvation previous to calling: there is a temporal salvation; a special providence attends the elect of God, as soon as born; God's visitation in a very special manner preserves their spirits; they are kept from many imminent dangers, and some of them from the grosser immoralities of life; and there is a chain of providences, as the fixing of their habitations, bringing to such a place, and under such a ministry, with various other things, ways and methods, which lead on to the effectual calling: and there is a preservation of them in Christ Jesus, antecedent to calling, Jde 1:1. God had a mind to save some; he pitched on his own Son to be the Saviour of them; he put those persons into his hands, where they are safely preserved; so as not to be damned, and everlastingly perish, notwithstanding their fall in Adam, their original corruption, and actual transgressions, until called by grace: yea, that spiritual and eternal salvation, which is by Jesus Christ, is before calling; this was resolved upon from eternity; a council of peace was formed; a covenant of grace was made; a promise of life given; persons were fixed upon to be saved; a Saviour was appointed, and blessings of grace were put into his hands; and all according to an eternal purpose. Salvation was not only resolved upon, but the scheme of it was contrived from eternity, in a way agreeable to all the divine perfections, in which Satan is most mortified, the creature abased, and the elect effectually saved; nay, salvation is obtained before calling, Christ being called to this work, and having undertook it, was in the fulness of time sent to effect it, and is become the author of it: the thing is done, and all that remain are the application of it, which is in the effectual calling, and the full possession of it, which will be in heaven. The calling here spoken of is not to an office, nor a mere call by the external ministry of the word, but a call by special grace, to special privileges, to grace and glory; and is an high and heavenly one, and is here called holy, for it follows, with an holy calling. The Vulgate Latin and Ethiopic versions read, "with his holy calling": the author of it is holy; it is a call to holiness, and the means of it are holy; and in it persons have principles of grace and holiness implanted in them; and are influenced to live holy lives and conversations: not according to our works; neither salvation nor calling are according to the works of men: not salvation; works are not the moving cause of it, but the free love and favour of God; nor the procuring cause of it, but the Lord Jesus Christ; nor the adjuvant or helping cause of it, for his own arm brought salvation alone: nor calling; which must be either according to works before, or after; not according to works before calling, for such are not properly good works, being destitute of faith in Christ, and proceeding neither from a right principle, nor to a right end; not according to works after calling, as they are after it they are the fruits of calling grace, and cannot be the cause, or rule, and measure at it: but according to his own purpose and grace; salvation is according to both: it is according to the purpose of God; God resolved upon the salvation of some; in pursuance of this resolution, he set up Christ as the Mediator; and it being necessary that he should be man, this was agreed to, and a body was prepared him; the time of his coming was fixed, called the fulness of time; and his sufferings and death, with all the circumstances of them, were determined by God. And it is according to grace; the resolution for it, and the contrivance of it, are owing to the grace of God; and which also appears in the making of a covenant; in setting up Christ as the Mediator of it; in the mission of him into this world; and in all the parts and branches of salvation: in the choice of persons to it; in the redemption of them by Christ; in their justification by his righteousness; in the pardon of their sins through his blood; in their adoption, regeneration, sanctification, and eternal glory; and the end of it is the glory of the grace of God. Vocation is also according to both the purpose and grace of God: it is according to his purpose; the persons called are fixed upon by him; whom he predestinates he calls; none are called, but whom God purposed to call; and for their calling no other reason can be assigned but the sovereign will of God, nor can any other reason be given why others are not called; the time of their calling is fixed in the decrees of God; and the place where, and means whereby, and occasion whereof, all are predetermined by him: and this is also according to grace; the author of it is the God of all grace; and in it is made the first discovery of grace to sinners; nothing out of God could move him to do it, and so it is sovereign grace; it is of some men, and not all, and so is distinguishing grace; it is of sinners, and so is free grace; and it is both to grace and glory, and so is rich grace: and it is according to grace which was given us in Christ Jesus before the world began; it is a gift, and a free gift, not at all depending upon any conditions in the creature, and entirely proceeding from the sovereign will of God; and it was a gift from eternity; there was not only a purpose of grace in God's heart, and a promise of it so early, but there was a real donation of it in eternity: and though those to whom it was given did not then personally exist, yet Christ did, and he existed as a covenant head and representative of his people; and they were in him, as members of him, as represented by him, being united to him; and this grace was given to him for them, and to them in him; in whom they were chosen, and in whom they were blessed with all spiritual blessings. The Ethiopic version reads, "in Christ Jesus, who before the world was"; but without any foundation.”
Source
1832
A.D.
Adam Clarke Methodist
1762–1832
“Who hath saved us - From sin; the spirit of bondage, and all tormenting fear. This is the design of the Gospel. And called us with a holy calling - Invited us to holiness and comfort here; and to eternal glory hereafter. Not according to our works - We have not deserved any part of the good we have received; and can never merit one moment of the exceeding great and eternal weight of glory which is promised. See the notes on the parallel passages. Before the world began - Προ χρονων αιωνιων. Before the Mosaic dispensation took place, God purposed the salvation of the Gentiles by Christ Jesus; and the Mosaic dispensation was intended only as the introducer of the Gospel. The law was our schoolmaster unto Christ, Gal 3:24. See the parallel places, and the notes there.”
Source
1871
A.D.
1871
“Who . . . called us--namely, God the Father (Gal 1:6). The having "saved us" in His eternal purpose of "grace, given us in Christ before the world began," precedes his actual "calling" of us in due time with a call made effective to us by the Holy Spirit; therefore, "saved us" comes before "called us" (Rom 8:28-30). holy calling--the actual call to a life of holiness. Heb 3:1, "heavenly calling" [TITTMANN, Greek Synonyms of the New Testament]; whereas we were sinners and enemies (Eph 1:18; Eph 4:1). The call comes wholly from God and claims us wholly for God. "Holy" implies the separation of believers from the rest of the world unto God. not according to--not having regard to our works in His election and calling of grace (Rom 9:11; Eph 2:8-9). his own purpose--The origination of salvation was of His own purpose, flowing from His own goodness, not for works of ours coming first, but wholly because of His own gratuitous, electing love [THEODORET and CALVIN]. grace . . . given us--in His everlasting purpose, regarded as the same as when actually accomplished in due time. in Christ--believers being regarded by God as IN HIM, with whom the Father makes the covenant of salvation (Eph 1:4; Eph 3:11). before the world began--Greek, "before the times (periods) of ages"; the enduring ages of which no end is contemplated (Co1 2:7; Eph 3:11).”
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.