The love of our neighbour worketh no evil. Love therefore is the fulfilling of the law.

“But that this is the first and greatest commandment, and that the next [has respect to love] towards our neighbour, the Lord has taught, when He says that the entire law and the prophets hang upon these two commandments. Moreover, He did not Himself bring down [from heaven] any other commandment greater than this one, but renewed this very same one to His disciples, when He enjoined them to love God with all their heart, and others as themselves. But if He had descended from another Father, He never would have made use of the first and greatest commandment of the law; but He would undoubtedly have endeavoured by all means to bring down a greater one than this from the perfect Father, so as not to make use of that which had been given by the God of the law. And Paul in like manner declares, "Love is the fulfilling of the law:" and [he declares] that when all other things have been destroyed, there shall remain "faith, hope, and love; but the greatest of all is love;" and that apart from the love of God, neither knowledge avails anything, nor the understanding of mysteries, nor faith, nor prophecy, but that without love all are hollow and vain; moreover, that love makes man perfect; and that he who loves God is perfect, both in this world and in that which is to come. For we do never cease from loving God; but in proportion as we continue to contemplate Him, so much the more do we love Him.”

“"God," then, being good, "is love," it is said. Whose "love worketh no ill to his neighhour," neither injuring nor revenging ever, but, in a word, doing good to all according to the image of God. "Love is," then, "the fulfilling of the law; " like as Christ, that is the presence of the Lord who loves us; and our loving teaching of, and discipline according to Christ. By love, then, the commands not to commit adultery, and not to covet one's neighbour's wife, are fulfilled, [these sins being] formerly prohibited by fear.”

“For there was no laying of accusations against each other among them, except what was friendly; neither ought there ever to be such among their followers or among believers: for the Lord says, "Do not that to another which thou wouldst not have done to thyself." And He says also, "Thou shalt love thy neighbour as thyself;" and, "Love worketh no ill to his neighbour."”

“"Love worketh no ill to his neighbor, therefore love is the fulfilling of the Law." Observe how it has both virtues, abstinence from evils (for it "worketh no ill," he says), and the working of good deeds. "For it is," he says, "the fulfilling (or filling up) of the Law;" not bringing before us instruction only on moral duties in a concise form, but making the accomplishment of them easy also. For that we should become acquainted with things profitable to us was not all that he was careful for (which is the Law's care), but also with a view to the doing of them it brought us great assistance; accomplishing not some part of the commandments, but the whole sum of virtue in us. Let us then love one another, since in this way we shall also love God, Who loveth us. For in the case of men, if you love a man's beloved, he that loveth him is contentious at it. But here He deemeth thee worthy to share His love, and hateth thee when thou sharest not. For man's love is laden with envy and grudging; but God's is free from all passion, whence also He seeketh for those to share His love. For He says, love thou with Me, and then thyself also will I love the more. You see the words of a vehement lover! If thou love My beloved, then will I also reckon Myself to be greatly beloved of thee. For He vehemently desireth our salvation, and this He showed from of old.”

“The rule of love is that one should wish his friend to have all the good things he wants to have himself and should not wish the evils to befall his friend which he wishes to avoid himself. He shows this benevolence to all men. No evil must be done to any. Love of one's neighbor works no evil. Let us then love even our enemies as we are commanded, if we wish to be truly unconquered.”

“Above, the Apostle showed how the faithful ought to observe justice toward their superiors; here he shows what they ought to render to all in common. And concerning this he does two things. First he sets down what he intends; second he gives the reason, at the words for he who loves. He says therefore first: it has been said, render to all their debts, not indeed partially, but in their entirety, and this is what he adds: owe no man anything. As if to say: pay all debts to all so fully that nothing remains which you ought to pay. And this for two reasons. First, because in the very delay of paying, sin is committed, since a man unjustly withholds what belongs to another. Hence it is said in Leviticus 19:13: the wages of thy hired man shall not abide with thee until the morning. And the same reasoning applies to other debts. Second, because as long as someone owes something, he is in a certain way a slave, and is bound to the one to whom he owes it. Proverbs 22:7: he that taketh a loan is servant to him that lendeth. There are, however, certain debts from which a man can never absolve himself. And this happens in two ways. In one way, on account of the excellence of the benefit, for which an equivalent recompense cannot be paid back: as the Philosopher says concerning the honor shown to God or to parents, according to that word of Psalm 115:12: what shall I render to the Lord for all that he has rendered to me? In another way, on account of the cause of owing, which always remains; or also because that which is rendered is never exhausted but always grows in the rendering. And for these causes the debt of fraternal love is paid in such a way that it is always still owed. First indeed because we owe love to our neighbor on account of God, to whom we cannot make sufficient recompense. For it is said in 1 John 4:21: this commandment we have from God, that he who loves God should love his brother also. Second, because the cause of love always remains, which is the likeness of nature and of grace. Ecclesiasticus 13:19: every beast loves its like, so also does every man love his neighbor. Third, because charity in loving does not fail but advances. Philippians 1:9: this I pray, that your charity may abound more and more. Therefore he says except that you love one another, because, that is, the debt of love is so paid once for all that it nevertheless always remains under the debt of the precept. John 15:12: this is my commandment, that you love one another. Then, when he says for he who loves, etc., he assigns the reason for what he had said, that we are never absolved from the debt of love, namely because in love consists the whole fulfilling of the law. Hence concerning this he does three things. First he sets forth what he intends; second he makes clear his proposition, at the words for thou shalt not commit adultery, etc.; third he draws the intended conclusion, at the words love therefore is the fulfilling of the law, etc. He says therefore first: it has therefore been said that we should not think ourselves free from the debt of love, as we are from other debts, for he who loves his neighbor has fulfilled the law, that is, the whole fulfilling of the law depends on love of neighbor. But this does not seem to be true. For it is said in 1 Timothy 1:5: the end of the commandment is charity. For each thing is perfected when it arrives at its end; and therefore the whole perfection of the law consists in charity. But charity has two acts, namely love of God and love of neighbor; hence the Lord also said in Matthew 22:40 that the whole law and the prophets hang on two commandments of charity, one of which concerns love of God, the other love of neighbor. It does not seem, therefore, that he who loves his neighbor fulfills the whole law. But it must be said that that love of neighbor which pertains to charity and fulfills the law is the love by which the neighbor is loved on account of God; and so in the love of neighbor the love of God is included, as a cause is included in its effect. For it is said in 1 John 4:21: and this commandment we have from God, that he who loves God should love his brother also. And, conversely, love of neighbor is included in love of God, as an effect is included in its cause; hence in the same place it is said: if any man shall say that I love God, and hateth his brother, he is a liar. And hence it is that in sacred Scripture mention is sometimes made only of the love of God, as if it sufficed for salvation, according to that word of Deuteronomy 10:12: and now, Israel, what doth the Lord thy God require of thee, but that thou fear the Lord thy God, and walk in his ways, and love him? And sometimes mention is made only of love of neighbor. John 15:12: these things I command you, that you love one another. Then, when he says for thou shalt not commit adultery, etc., he proves his proposition. First indeed by induction; second by the middle term of a syllogism, at the words love of neighbor, etc. Concerning the first, in the manner of those who use induction, he enumerates certain precepts which fulfill the love of neighbor. And because the three precepts of the first table are more immediately ordered to the love of God, he makes no mention of them here, although they too are fulfilled in the love of neighbor, insofar as the love of God is included in the love of neighbor. He enumerates, however, the commandments of the second table, but omits the affirmative precept only which concerns the honor of parents, in which too it is understood that we should render to all what we owe them. He enumerates, moreover, the negative precepts, by which someone is forbidden to inflict evil on his neighbors. And this for a twofold reason. First indeed, because negative precepts are more universal, both as to times and as to persons. As to times indeed, because negative precepts oblige always and for always. For at no time is one to steal or commit adultery. Affirmative precepts, however, oblige indeed always, but not for always, but according to place and time; for a man is not bound to honor his parents at every time, but according to place and time. As to persons, however, because no man is to be harmed, but we are not sufficient that one man could serve all men. Second, because it is more evident that the negative precepts are fulfilled through love of neighbor than the affirmative ones. For he who loves someone abstains the more from doing him harm, than he bestows benefits on him, from which a man is sometimes hindered by lack of power. Now in three ways can someone inflict harm on his neighbor. In one way, by deed; in another way, by word; third, by desire. By deed indeed in three ways. In one way as regards the person of the neighbor himself, and this is forbidden when it is said thou shalt not kill. In which too is understood to be forbidden every injury inflicted on the person of a neighbor. 1 John 3:15: no murderer hath eternal life abiding in himself. Second, as regards a person joined to him, namely his wife, and this is forbidden when it is said thou shalt not commit adultery. In which too is understood to be forbidden fornication and every illicit use of the genital members. Hebrews, last chapter: fornicators and adulterers God will judge. Third, as regards external things, which is forbidden when it is said thou shalt not steal. In which too is forbidden every unjust taking away of another's property, whether by force or by fraud. Zechariah 5:3: every thief, as it is written there, shall be judged. Harm, however, which someone inflicts on his neighbor by word, is forbidden when it is said thou shalt not speak false testimony. Which is forbidden not only in judgment but also outside judgment, whether by way of detraction or by way of insult. Proverbs 19:5: a false witness shall not be unpunished, and he that speaketh lies shall not escape. Harm, however, which someone inflicts on his neighbor by desire alone, is forbidden when it is said thou shalt not covet thy neighbor's goods. Where too is understood to be forbidden the coveting of his wife; above, chapter 7:7: for I knew not concupiscence, namely, that it was a sin, unless the law said: thou shalt not covet. These commandments are set down in Exodus 20:17ff. Having enumerated several precepts, he gathers all the others together in common, saying and if there be any other commandment, whether affirmative or negative, or pertaining to God or to neighbor, in the manner said above, it is renewed, that is, it is perfected and fulfilled, in this word: thou shalt love thy neighbor as thyself. Which indeed is set down in Leviticus 19:18, where we have: thou shalt love thy friend as thyself. Now what he says thy neighbor is to be referred to every man and also to the holy Angels, as Augustine proves in Book I of On Christian Doctrine. For by the name of neighbor is understood whoever shows mercy to someone, according to that word of Luke 10:36: which of these three, in thy opinion, was neighbor to him that fell among robbers? And he said: he that shewed mercy to him, etc. And because a neighbor is neighbor to a neighbor, it follows that he too, who receives mercy from someone, is called that one's neighbor. Now the holy Angels bestow mercy upon us, and we ought to bestow mercy upon all men and to receive it from them when it is necessary. Hence it is clear that both the holy Angels and all men are called our neighbors, because the beatitude to which we tend, they either already possess, or they tend toward it together with us. From which it is clear that the demons, according to this reasoning, are not our neighbors, nor is love of them enjoined upon us under this precept, because they are totally excluded from the love of God and are not to be counted in the number of neighbors, but in the number of enemies. Now what he says as thyself is not to be referred to an equality of love, as though someone were bound to love his neighbor equally with himself: for this would be against the order of charity, by which each is more bound to care for his own salvation than for the salvation of others. Song of Songs 2:4: he set in order charity in me. But it is to be referred to a likeness of love, namely that we should love our neighbor in a manner like that in which we love ourselves. And this in three ways. First indeed as to the end of love, namely that we should love both ourselves and our neighbor on account of God. Second as to the form of love, namely that just as someone loves himself, as it were willing good to himself, so should someone love his neighbor, as it were willing good things to him. But he who loves his neighbor only in order that he may possess his usefulness or his affection, does not will good to his neighbor, but wills good for himself from his neighbor. In which manner indeed a man is said to love irrational things, for instance wine or water, namely so as to make use of them. Third as to the effect of love, namely that someone should come to the aid of his neighbor's need, as he would to his own, and that he should commit nothing unlawful out of love for his neighbor, just as he ought not on account of love of himself. Then, when he says love of neighbor, etc., he makes clear his proposition by the middle term of a syllogism, in this manner: he who loves his neighbor works no evil toward him. But every precept of the law tends to this, that one abstain from evil. He therefore who loves his neighbor has fulfilled the law. Now that the love of neighbor works no evil is had in 1 Corinthians 13:4: charity dealeth not perversely, etc. In whatever way evil is here taken, whether for the evil of transgression, or also of omission, this can be referred not only to the negative precepts but also to the affirmative ones. But insofar as love of neighbor includes love of God, it is understood that love of neighbor excludes evil, not only that which is against the neighbor, but also that which is against God. And thus the precepts of the first table are also included. Last, he draws the conclusion principally intended, saying love therefore is the fulfilling of the law, that is, through love the law is fulfilled and perfected. Ecclesiasticus 24:16: in the fullness of the saints is my abode. Colossians 3:14: have charity, which is the bond of perfection.”

“Love worketh no ill to his neighbour,.... That is, the man that truly loves his neighbour, will contrive no ill against him, nor do any to him; he will not injure his person, nor defile his bed, nor deprive or defraud him of his substance; or do hurt to his character, bear false testimony against him, or covet with an evil covetousness anything that is his; but, on the contrary, will do him all the good he is capable of: therefore love is the fulfilling of the law: so far as a man loves his neighbour, he acts agreeably to the law, and the particular precepts of it above mentioned: what the apostle says of love to the neighbour, the Jews frequently say of love to God; "he that loveth God (they say (d)) , "hath fulfilled the decalogue", both above and below.'' And again (e), "there is no service like the love of God, R. Abba saith it is , "the sum of the law"; for the ten words of the law , "are herein comprehended", or "fulfilled":'' and elsewhere (f) they observe, "that , "the whole law is comprehended", or fulfilled "in love".'' (d) Zohar in Deut. fol. 111. 3. (e) Zohar in Deut. fol. 113. 1. (f) Moses Kotsensis Mitzvot Tora, praecept. affirm. 3. prope finem.”