Matthew Poole and continuators on Galatians 5:14

14 For all the law is fulfilled in one word, even in this, Thou shalt love thy neighbour as thy self .

The whole Will of God, containing our duty towards men, is reducible to this one thing, Love; for whatsoever God hath commanded us to do towards men, is but a branch from this root, and must flow from Love as its principle. Or the whole will of God concerning man is fulfilled in this one thing of love; where love to God is not excluded, but supposed, as the root of our love to our Neighbour; for our Neighbour is to be loved for God. Thus Rom. 13.8. He that loveth another, hath fulfilled the Law: And 1 Ioh. 4.20. the Apostle proveth, that a man cannot love God unless he loveth his Brother; and 1 Tim. 1.5. The end of the Commandment is charity ▪ Yet what the Papists would conclude from hence, (viz. that it is possible for a man to fulfil the Law, because it is possible for him to love his Neighbour;) doth by no means follow; for the Apostle 1 Tim. 1.5. telleth us, This love must proceed out of a pure heart, and of a good conscience, and faith unfeigned. Mr. Calvin observeth well, that the Apostle here mentioneth love to men as the fulfilling of the Law, in opposition to the false Teachers; who made the fulfilling of the Law to lye in the observance of the ceremonies of the law, whereas the great thing which the law of God requireth is love, out of a pure heart, good conscience, and faith unfeigned. So that he who believeth with a Faith unfeigned, and out of that principle, with a pure heart, and a good conscience, loveth his Neighbour as himself, shall be by God accounted to have fulfilled the law; for love is the end of the law.

Marginal references: Matth. 7.12. Jam. 2.8.; Levit. 19.18. Mat. 22.37, 39.