Christ came “not to abolish the Law and the Prophets … but to fulfill them.”
If you hear me say “I didn’t do it!” it’s a safe bet someone claims I did. In saying that he has come “not to abolish the Law and the Prophets … but to fulfill them” (Mt 5:17), Jesus’ words fit this pattern well. But what is it in his teaching that invites this charge? After all, doesn’t he say as well that “unless your righteousness exceeds that of the scribes and Pharisees, you will never enter the kingdom of heaven” (MT 5:20)? Far from abrogating them, these words intensify the demands of the Law.
In the Sermon on the Mount, Jesus’ claim to fulfill the law comes on the heels of the Beatitudes. Most all of what is taught is those verses echoes central tenets of the Mosaic Law and are summed up in the praise of “righteousness” (Mt 5:6, 10), a word that refers to one’s adherence to what the Law commands. (So, again, “unless your righteousness exceed that of the scribes and Pharisees …”)
What is new in the Beatitudes appears at the end. Jesus praises those who are “persecuted for righteousness’ sake” (5:10). And then, in keeping with that tendency of Semitic thought to offer one idea in two parallel expressions, Jesus repeats himself. But instead of praising those “persecuted for the keeping or the Mosaic Law,” he says, “Blessed are you when men revile you and persecute you and utter all kinds of evil against you falsely on my account” (Mt 5:11).
Jesus claims that it is fidelity to himself that is the content of righteousness. And as the prophets were persecuted for exhorting Israel to keep faithfulness to the Law, so now the disciples of Jesus will be persecuted for exhorting fidelity to Christ. “Rejoice and be glad, for your reward is great in heaven, for so men persecuted the prophets who were before you” (Mt 5:12)
And it is here, after he seems to substitute fidelity to himself for fidelity to the Law, that Jesus goes on to say that the one isn’t opposed to the other. “Think not that I have come to abolish the Law; I have come not to abolish the Law but to fulfill it” (Mt 5:17). But how?
In both the Old and the New Testament, love is recognized as the heart of the Law. In response to the question, “Teacher, which is the great commandment in the law?” Jesus answers by saying, “You shall love the Lord your God with all your heart, and with all your soul, and with all your mind. This is the great and first commandment. And a second is like it, You shall love your neighbor as yourself. On these two commandments depend all the law and the prophets” (Mt 22:36-40).
While we hear these words in the New Testament, they are from the beginning, a teaching of the Old. In the Shema prayer we hear the command to “love the LORD your God with all your heart, and with all your soul, and with all your might”(Dt 6:5). In Leviticus, we are commanded to “love your neighbor as yourself” (Lev 19:18).
If Christ, as St. Paul teaches, is “the end of the law” (Rom 10:4), he is so precisely because he is both the exemplar of such love and the One in whom the performance of such love is made possible in us as well. Said in the language of Scripture, “I am the vine, you are the branches” (Jn 15:5), and since “Greater love has no man than this” (Jn 15:13), “love one another as I have loved you” (Jn 15:12). Jesus is the Law’s “end,” which is to say its goal, the reality toward which the Law leads and in whom it is not abolished but fulfilled.
What though of the content of the Law, all of which we retain as inspired Scripture? St. Augustine is right in his exhortation “love, and do what you will” (In Ep Ioannes, VII, 8), but the “freedom” for which “Christ has set you free” (Gal 5:1) is not without specific and necessary forms. If in one sense the precepts of the Law have passed away (Gal 3:25), they have done so precisely by being given new and definitive shape in Christ. (In this way there is no opposition of Law and gospel, but only a succession of gifts—in the words of John 1:16, “grace upon grace.”)
Following St. Thomas, we can speak of the law as belonging as it were to three categories: moral, judicial, and ceremonial (Summa Theologica, I-II, 99).
“Moral” precepts pertains to that what is universal. These remain; we, for example, keep the Ten Commandments.
“Judicial” precepts are an application of the universal; we honor our father and mother (Ex 20:12), but we are not bound to enforce this universal command in the same way as Israel once did, e.g. “Whoever curses his father or his mother shall be put to death” (Ex 21:17).
Lastly, the “ceremonial” precepts pertain to the cultic life of Israel. These are transfigured in Christ. As St. Paul says, for example, “Christ our Paschal lamb has been sacrificed” (1 Cor 5:7). The celebration of the Eucharist is new Passover meal that recapitulates the old. Or as we have just seen, the celebration of the Pentecost recalls the giving of the first Law at Sinai even as it celebrates the gift of the new Law, the Holy Spirit. The Old Law—good and holy in itself (Rom 9:4; Gal 3:21)—is taken up in the New.
If one would follow Christ, their “righteousness must exceed that of the scribes and Pharisees,” for Christ came “not to abolish the Law and the Prophets … but to fulfill them.”