Matthew 5:17

Not to destroy the law, &c. It is true, by Christ's coming, a multitude of ceremonies and sacrifices, and circumcision, were to cease; but the moral precepts were to continue, and to be complied with, even with greater perfection. (Witham) --- To fulfil. By accomplishing all the figures and prophecies, and perfecting all that was imperfect. (Challoner) --- Our Saviour speaks in this manner, to prepare the minds of the Jews for his new instructions. For although they were not very solicitous about fulfilling the law, still they were extremely jealous of any change exacted a more perfect morality. Our Lord fulfilled the law three several ways: 1. By his obedience to the prescribed rites; therefore he says, it behoveth us to fulfil all justice: and who shall accuse me of sin? 2. He observes the law, not only by his own observance of it, but likewise by enabling us to fulfil it. It was the wish of the law to make man just, but found itself too weak; Christ therefore came justifying man, and accomplished the will of the law. 3. He fulfilled the law, by reducing all the precepts of the old law to a more strict and powerful morality. (St. John Chrysostom, hom. xvi.)