The interpretation timeline
Romans 12:15 Douay-Rheims

Rejoice with them that rejoice; weep with them that weep.

A.D. 220 – 1871 6 witnesses 7 excerpts

Patristic

before A.D. 750
220
A.D.
Tertullian Patristic
c. A.D. 150–220
“The first point, indeed, on which I shall join issue is this: whether a servant of God ought to share with the very nations themselves in matters of his kind either in dress, or in food, or in any other kind of their gladness. "To rejoice with the rejoicing, and grieve with the grieving," is said.”
“(And how worthy a thing is this, that, under the auspices of faith, men should congregate from all quarters to Christ! "See, how good and how enjoyable for brethren to dwell in unity!" This psalm you know not easily how to sing, except when you are supping with a goodly company!) But those conclaves first, by the operations of Stations and fastings, know what it is "to grieve with the grieving," and thus at last "to rejoice in company with the rejoicing." If we also, in our diverse provinces, (but) present mutually in spirit, observe those very solemnities, whose then celebration our present discourse has been defending, that is the sacramental law.”
Source
407
A.D.
John Chrysostom Patristic
A.D. 347–407
“"Rejoice with them that do rejoice, and weep with them that weep." Since it is possible to bless and not to curse, and yet not to do this out of love, he wishes us to be penetrated with the warmth of friendship throughout. And this is why he goes on in these words, that we are not only to bless, but even feel compassion for their pains and sufferings, whenever we happen to see them fallen into trouble. Yes, it will be said, but to join in the sorrows of mourners one can see why he ordered them, but why ever did he command them the other thing, when it is no such great matter? Aye, but that requires more of a high Christian temper, to rejoice with them that do rejoice, than to weep with them that weep. For this nature itself fulfils perfectly: and there is none so hard-hearted as not to weep over him that is in calamity: but the other requires a very noble soul, so as not only to keep from envying, but even to feel pleasure with the person who is in esteem. And this is why he placed it first. For there is nothing that ties love so firmly as sharing both joy and pain one with another. Do not then, because thou art far from difficulties thyself, remain aloof from sympathizing too. For when thy neighbor is ill-treated, thou oughtest to make the calamity thine own. Take share then in his tears, that thou mayest lighten his low spirits. Take share in his joy, that thou mayest make the joy strike deep root, and fix the love firmly, and be of service to thyself rather than to him in so doing, by thy weeping rendering thyself merciful, and by thy feeling his pleasure, purging thyself of envy and grudging. And let me draw your attention to Paul's considerateness. For he does not say, Put an end to the calamity, lest thou shouldest say in many cases that it is impossible: but he has enjoined the easier task, and that which thou hast in thy power. For even if thou art not able to remove the evil, yet contribute tears, and thou wilt take the worst half away. And if thou be not able to increase a man's prosperity, contribute joy, and thou wilt have made a great addition to it. Therefore it is not abstaining from envy only, but what is a much greater thing that he exhorts us to, namely, joining in the pleasure. For this is a much greater thing than not envying.”
Source

Scholastic

c. 1100 – 1500
1273
A.D.
Thomas Aquinas Catholic
1225–1274
“Above, the Apostle showed how charity is to be shown to those in need; now he shows how it is to be shown even to enemies. And first he sets down an admonition; second he proves what he said, at the words for it is written. Concerning the first, it must be considered that three things pertain to charity. First, indeed, benevolence, which consists in this, that one wills good for another and does not will evil for him; second, concord, which consists in this, that friends will and not-will the same things; third, beneficence, which consists in this, that one does good to the one he loves and does not harm him. First, therefore, he sets down the things that pertain to benevolence; second, the things that pertain to concord, at rejoice with those who rejoice; third, the things that pertain to beneficence, at render evil to no one, and so on. Concerning the first he does two things. First he admonishes that benevolence should be ample, extending itself even to enemies, when he says bless those who persecute you. Concerning which it must be noted that to bless is to speak good. Now it happens that one speaks good in three ways. In one way by declaring, as when someone praises another's good, as in Sirach 31:28: the lips of many shall bless him that is splendid in bread distribution, and his testimony of truth is faithful. In another way by commanding, and thus to bless by authority is proper to God, from whose command good is derived to creatures; but the ministry pertains to the ministers of God, who invoke the name of the Lord over the people. Numbers 6:22-26: thus shall you bless the children of Israel, and you shall say to them: the Lord bless you, and keep you. May the Lord show his face to you, and have mercy on you. May the Lord turn his countenance to you, and give you peace. And afterward: they shall invoke my name upon the children of Israel, and I will bless them. Third, one blesses by wishing well. Psalm 128:8: and they that passed by said not, the blessing of the Lord be upon you. And according to this, to bless is to will good for someone, and as it were to pray for good on someone's behalf. And it is taken in this way here. Hence in what is said, bless those who persecute you, it is given to understand that we ought to be benevolent even toward enemies and persecutors, wishing good things for them and praying for them. Matthew 5:44: love your enemies, and pray for those who persecute and slander you. Now what is said here is in one respect under precept, and in another respect under counsel. For that one should show, in a general way, an affection of love toward enemies, not excluding them from the common love of neighbors and from the common prayer that one makes for the faithful, pertains to the necessity of precept. Likewise also that one should, in an article of necessity, show the effect of love in a particular way even to an enemy, pertains to the necessity of precept. Hence it is said in Exodus 23:4: if you meet your enemy's ox, or his ass going astray, you shall bring it back to him. But that one should show, in a special way, an affection of love and the support of prayer, or any benefit of assistance whatsoever, to an enemy, sometimes even outside an article of manifest necessity, pertains to the perfection of counsels: because through this is shown a charity of man toward God so perfect that it overcomes all human hatred. But he who repents and asks for mercy is no longer to be counted among enemies or persecutors. Hence the signs of charity are to be shown to him without any difficulty. Sirach 28:2: forgive your neighbor when he hurts you, and then your sins shall be forgiven when you pray. Second, he teaches that benevolence or blessing should be pure, that is, without admixture of its contrary. Hence he says bless, and do not curse, that is, bless in such a way that you in no way curse. This is against certain people who bless with the mouth and curse in the heart, according to Psalm 27:3: who speak peace with their neighbor, but evils are in their hearts. And also against those who sometimes bless, sometimes curse, or bless some and curse others. James 3:10: out of the same mouth proceeds blessing and cursing; my brothers, these things ought not to be so. 1 Peter 3:9: not rendering curse for curse. But against this it seems that in sacred Scripture many curses are found. For it says in Deuteronomy 27:26: cursed be he who does not abide by the words of this law, nor fulfills them in deed. To this it must be said that to curse is to speak evil; and this, like blessing, happens in three ways, namely by declaring, by commanding, and by wishing; and according to each of these ways it can be done well or badly. For if that which is materially evil is called evil in any of the aforesaid ways, it is not unlawful under the aspect of good, because this is rather to bless than to curse: for each thing is judged more according to its form than according to its matter. But if someone speaks evil under the aspect of evil, he formally curses; hence it is altogether unlawful. Now both of these occur in this, that one declares evil by way of assertion. For sometimes one declares another's evil in order to make known a necessary truth, and thus speaks evil under the aspect of a necessary truth, which is good, hence it is lawful. And in this way it is said in Job 3:1 and following, that Job cursed his day, declaring the wretchedness of the present life, just as the Apostle says in Ephesians 5:16: redeeming the time, because the days are evil. But sometimes one declares another's evil under the aspect of evil, namely with the intention of detraction. And this is unlawful. For it is said in 1 Corinthians 6:10: neither the cursed, nor the rapacious, shall possess the kingdom of God. Likewise also in this, that one speaks evil by way of command; now it happens sometimes that one speaks what is materially evil under the aspect of good, as when, by someone's command, an evil of punishment comes upon another for the sake of justice, which indeed is lawful. And in this way transgressors of the law are cursed, that is, they are assigned to punishment according to justice. But sometimes one, by commanding, speaks another's evil unjustly, as on account of hatred and vengeance. And such a curse is unlawful. Exodus 21:17: he who curses his father or mother shall die the death. And the same holds also concerning that which one speaks as evil by way of wishing. For if one wishes this under the aspect of good, as that through someone's adversity he may come to spiritual profit, this is lawful. Job 5:3: I have seen a fool with a firm root, and I cursed his beauty at once. But if a man does this on account of hatred or vengeance, it is altogether unlawful. 1 Kings 17:43: the Philistine cursed David by his gods. Then, when he says rejoice with those who rejoice, and so on, he sets down the things that pertain to concord. And first he sets down the teachings of concord; second he removes the impediments, at not minding high things, and so on. Now concord can be considered in two ways. In one way as to its effect in good things and in evil things. In good things indeed, that one should rejoice together with the goods of others; hence he says rejoice, that is, you ought, with those who rejoice. Philippians 2:17: I rejoice and congratulate you all. But this must be understood as applying when someone rejoices over a good. Now there are some who rejoice over evil, according to Proverbs 2:14: who are glad when they have done evil, and rejoice in most wicked things. And with these one ought not to rejoice together. In 1 Corinthians 13:6 it is said of charity that it does not rejoice over iniquity, but rejoices together with the truth. In evil things, however, that one should grieve over another's evils. Hence he adds, weep, that is, you ought, with those who weep. Job 30:25: I wept formerly for him that was afflicted. Sirach 7:38: be not wanting in comforting them that weep, and walk with them that mourn. For the very compassion of a friend grieving together brings comfort in sorrows in two ways: first indeed, because from this an effective proof of friendship is gathered. Sirach 12:9 in his misfortune, that is, in his misfortune, a friend is known. And this very thing is delightful to know, that someone is a true friend to oneself. In another way, because from this very fact that a friend grieves together, he seems to offer himself to bear together the burden of adversity that causes the sorrow. And indeed what is borne by many is borne more lightly than what is borne by one alone. Second, concord consists in unity of judgment, and as to this he says the same thing, that is, be of the same mind, minding the same thing toward one another, namely that you agree in the same judgment. 1 Corinthians 1:10: that you be perfect in the same mind, and in the same judgment. Philippians 2:2: having the same charity, being of one mind, minding the same thing. It must be known, however, that judgment is twofold. One indeed pertains to the judgment of the intellect concerning speculative matters, as concerning considerations of geometry or of natural science: to disagree in such matters is not repugnant to friendship or charity, because charity is in the will. Now judgments of this kind do not proceed from the will, but from the necessity of reason. But the other judgment pertains to the judgment of reason concerning things to be done, and in such matters disagreement is contrary to friendship, because such disagreement involves a contrariety of will. And because faith is not only speculative but also practical, insofar as it works through love, as is said in Galatians 5:6, therefore also to disagree from right faith is contrary to charity. Then, when he says not minding high things, and so on, he excludes the impediments to concord, which indeed are two. The first is pride, from which it happens that, while someone inordinately seeks his own excellence and shuns subjection, he wills another to be subjected and to hinder that other's excellence. And from this discord follows. Proverbs 13:10: among the proud there are always quarrels. And therefore, to remove this, he says do not mind high things, that is, that you should not inordinately seek your own excellence. Above, in chapter 11:20: do not be high-minded, but fear. Sirach 3:22: seek not the things that are too high for you. But be consenting to the humble, that is, to those things which are humble, that is, do not refuse those things which seem lowly, when it is fitting. Psalm 83:11: I have chosen to be abject in the house of my God. 1 Peter, last chapter: humble yourselves under the mighty hand of God, and so on. The second impediment to concord is presumption of wisdom, or even of prudence, from which it happens that one does not believe the judgment of others. To remove this he says, be not wise in your own conceits, that is, that you should judge that only to be prudence which seems so to yourselves. Isaiah 5:21: woe to you that are wise in your own eyes, and prudent in your own conceits. Above, in chapter 11:25: that you may not be wise in your own conceits. Then, when he says render to no one evil for evil, and so on, he teaches the things that pertain to beneficence, by excluding its contrary. And first he teaches that no one should be done evil by reason of vengeance; second he teaches that no one should be done evil by reason of defense, at not defending yourselves. Concerning the first he does three things. First he forbids vengeance, saying rendering to no one evil for evil, namely you should be. Psalm 7:5: if I have rendered to them that repaid me evils. 1 Peter 3:9: not rendering evil for evil. But this must be understood formally, just as was said above concerning cursing: for we are forbidden to render evil for evil out of a disposition of hatred or envy, in such a way that we delight in another's evil. But if, for the evil of the fault that someone commits, a judge renders the evil of punishment according to justice, to compensate for the wickedness, he materially indeed inflicts an evil, but formally and of itself he inflicts a good. Hence when a judge hangs a thief for homicide, he does not render evil for evil, but rather good for evil. And in this way the Apostle handed over a certain man, for the sin of incest, to Satan for the destruction of the flesh, that the spirit might be saved, as is found in 1 Corinthians 5:5. Second, he teaches that goods should also be shown to neighbors, saying providing, that is, you should be, good things not only before God, that is, that you should take care to satisfy your conscience before God, but also before all men, that is, that you should do the things that please men. 1 Corinthians 10:32-33: be without offense to the Jews, and to the Gentiles, and to the Church of God, as I also in all things please all men. 2 Corinthians 8:21: providing good things not only before God, but also before all men. This, however, can happen both well and badly. For if this is done on account of human favor, it is not done well. Matthew 6:1: take heed that you do not do your justice before men, to be seen by them. But if this is done for the glory of God, it is done well, according to Matthew 5:16: so let your light shine before men, that they may see your good works, and glorify your Father who is in heaven. Third, he assigns the reason for both of the things said. For we ought to abstain from the repayment of evils, and to provide good things before men, for this reason, that we may have peace with men, and therefore he adds, having peace with all men. Hebrews, last chapter: follow peace with all men. But here he adds two things, of which the first is that he says if it can be done. For sometimes the wickedness of others prevents us from being able to have peace with them, namely because peace cannot be had with them unless one consents to their wickedness, which peace indeed is plainly unlawful. Hence the Lord says in Matthew 10:34: I came not to send peace, but the sword. The other thing he adds, saying that is of you, namely that even if they themselves act against peace, nevertheless what is in us we ought to do, so that we may seek peace with them. Psalm 119:7: with them that hated peace, I was peaceable. And elsewhere: seek peace and pursue it. Then, when he says not defending yourselves, and so on, he shows that evils are not to be inflicted on neighbors by way of defense. And first he sets down the teaching, saying do not defend yourselves, most beloved, just as it is said of Christ in Isaiah 50:6: I have given my body to the strikers, and my cheeks to them that plucked them. And Isaiah 53:7: he was dumb as a lamb before the one that shears him, and so on. Hence also the Lord himself commanded in Matthew 5:39: if anyone strikes you on one cheek, offer him the other also. But, as Augustine says in the book Against Lying, those things which were done by the saints in the New Testament are of value as examples for understanding the Scriptures, which are given in precepts. Now the Lord himself, when he had been struck with a blow, did not say, behold the other cheek; but said, if I have spoken evil, give testimony of the evil; but if well, why do you strike me? In which he shows that the preparation of the other cheek is to be made in the heart. For the Lord was prepared, not only to be struck on the other cheek for the salvation of man, but to be crucified in his whole body. And as Augustine says to Marcellinus, this commandment is then rightly fulfilled when it is believed that it will be of profit to him for whose sake it is done, for working correction and concord in him, even if another outcome should follow. These precepts of patience, therefore, are always to be kept in the preparation of the heart, and that very benevolence, that evil not be rendered for evil, is always to be fulfilled in the will. But many things must also be done, even to the unwilling, to be corrected with a certain benevolent harshness. Second, he assigns the reason, when he says but give place to wrath, that is, to the divine judgment. As if he were saying: commit yourselves to God, who by his judgment can defend and avenge you, according to 1 Peter, last chapter: casting all your care upon him, for he has care for you. But these things must be understood in the case in which we do not have the ability to act otherwise according to justice; but because, as is said in Deuteronomy 1:17, judgment is God's, when someone, by the authority of a judge, seeks vengeance to restrain wickedness and not out of hatred, or even, with the authority of some superior, procures his own defense, he is understood to give place to wrath, that is, to divine judgment, whose ministers are the princes, as is said below in chapter 13:4. Hence also Paul procured that he be defended by armed men against the plots of the Jews, as appears in Acts 23:12 and following. Then, when he says as it is written, and so on, he proves what he had said. And first by authority; second by reason, at be not overcome by evil, and so on. Concerning the first he does two things. First he proves what was said about the prohibition of vengeance, saying, it is said: give place to wrath, that is, to divine judgment, for it is written, Deuteronomy 32:35, vengeance is mine, namely, keep it, and I will repay, says the Lord. Our text reads thus: vengeance is mine, and I will repay them in due time. Psalm 93:1: the Lord is the God of revenges. Nahum 1:2: God is jealous and the Lord revenges. Second he proves by authority what was said about showing benevolence to enemies. In which authority indeed, first, he sets down the teaching that we should come to the aid of enemies in an article of necessity, because this is of the necessity of precept, as was said above. And this is what he says, but if your enemy is hungry, feed him; if he thirsts, give him drink. Matthew 5:44: do good to them that hate you. Second he assigns the reason, saying, for in doing this, you shall heap coals of fire upon his head. This indeed can be understood in one way as an evil, so that the sense would be: if you do good to him, your good will be turned to evil for him, because from this he will incur the burning of eternal fire through his ingratitude. But this sense is repugnant to charity, against which one would act who assisted someone so that it should turn to that person's evil. And therefore it must be expounded as a good, so that the sense is, for in doing this, that is, coming to his aid in necessity, coals of fire, that is, the love of charity, of which it is said in Canticles 8:6, its lamps are as lamps of fire and flames, you shall heap, that is, you shall gather, upon his head, that is, upon his mind. Because, as Augustine says in the book On Catechizing the Uninstructed, there is no greater inducement to loving than to be first in loving. For too hard is the mind that, even if it was unwilling to bestow love, is unwilling to repay it. Then, when he says be not overcome by evil, and so on, he proves what he said by reason. For it is natural to man to will to overcome his adversary and not to be overcome by him. Now that thing is overcome by another which is drawn to that other, just as water is overcome by fire when it is drawn to the heat of fire. If, therefore, some good man, on account of the evil that is inflicted on him by someone, is drawn to this, that he does evil to him, the good is overcome by the evil. But if, on the contrary, on account of the kindness that the good man shows to his persecutor, he draws that persecutor to love of himself, the good man overcomes the evil. He says, therefore, be not overcome by the evil of him who persecutes you, so that you should persecute him, but in your good overcome his evil, namely, that by doing good to him, you draw him away from evil. 1 John, last chapter: this is the victory that overcomes the world, our faith. Jeremiah 15:19: they shall be turned to you, and you shall not be turned to them.”

Post-Reformation

c. 1650 – 1900
1771
A.D.
John Gill Reformed
1697–1771
“Rejoice with them that do rejoice,.... Not in anything sinful and criminal, in a thing of nought, in men's own boastings; all such rejoicing is evil, and not to be joined in; but in things good and laudable, as in outward prosperity; and to rejoice with such, is a very difficult task; for unless persons have a near concern in the prosperity of others, they are very apt to envy it, or to murmur and repine, that they are not in equal, or superior circumstances; and also in things spiritual, with such who rejoice in the discoveries of God's love to their souls, in the views of interest in Christ, and of peace, pardon, and righteousness by him, and in hope of the glory of God; when such souls make their boast in the Lord, the humble hearing thereof will be glad, and will, as they ought to do, join with them in magnifying the Lord, and will exalt his name together: and weep with them that weep; so Christ, as he rejoiced with them that rejoiced, at the marriage in Cana of Galilee, wept with them that wept, with Mary at the grave of Lazarus. The design of these rules is to excite and encourage sympathy in the saints with each other, in all conditions inward and outward, and with respect to things temporal and spiritual; in imitation of Christ their great high priest, who cannot but be touched with the infirmities of his people; and as founded upon, and arising from, their relation to each other, as members of the same body; see Co1 12:26;”
Source
1832
A.D.
Adam Clarke Methodist
1762–1832
“Rejoice with them that do rejoice - Take a lively interest in the prosperity of others. Let it be a matter of rejoicing to you when you hear of the health, prosperity, or happiness of any brother. Weep with them that weep - Labour after a compassionate or sympathizing mind. Let your heart feel for the distressed; enter into their sorrows, and bear a part of their burdens. It is a fact, attested by universal experience, that by sympathy a man may receive into his own affectionate feelings a measure of the distress of his friend, and that his friend does find himself relieved in the same proportion as the other has entered into his griefs. "But how do you account for this?" I do not account for it at all, it depends upon certain laws of nature, the principles of which have not been as yet duly developed.”
Source
1871
A.D.
1871
“Rejoice with them that rejoice; and weep--the "and" should probably be omitted. with them that weep--What a beautiful spirit of sympathy with the joys and sorrows of others is here inculcated! But it is only one charming phase of the unselfish character which belongs to all living Christianity. What a world will ours be when this shall become its reigning spirit! Of the two, however, it is more easy to sympathize with another's sorrows than his joys, because in the one case he needs us; in the other not. But just for this reason the latter is the more disinterested, and so the nobler.”
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.