Is the baptized Jew obligated to keep the commandments of Jewish Law? Ask a priest and he’ll probably tell you, “No, of course not.” But, “in the beginning,” it wasn’t so. In the beginning, the disciples of Jesus were “zealous for the Law.” That’s what St. James tells us in Acts 21. So let’s take a good look at this question.
First of all, did Jesus keep the commandments? Yes. He clearly did, and the Church agrees.
Here’s what the Commission for Religious Relations with the Jews has to say in a document issued in 1985, “Notes on the correct way to present the Jews and Judaism in preaching and catechesis in the Roman Catholic Church’’:
The Commission speaks of Jesus “inviting obedience to the Law.” That might sound as though he wasn’t very insistent on it. But that would be a misunderstanding. The same word is used in the Catechism of the Catholic Church to refer to faith and conversion, and Jesus was certainly insistent about that.
“...Indeed, Christ invited people to faith and conversion, but never coerced them. For he bore witness to the truth but refused to use force to impose it on those who spoke against it...” (CCC 160)
So, the Catechism uses the word “invited,” but Jesus was very straightforward about it: he called for the observance of the Law.
With this magisterial document in mind, look at Matthew 5 and Matthew 23 again, and you see just how serious Jesus was about keeping the Law (He was, of course, addressing Jews, his disciples among them. Gentiles, Christian or otherwise are certainly not obligated to keep the Law of the Torah. What G-d wants of the Gentile He has taught through the Church. )
 "Think not that I have come to abolish the law and the prophets; I have come not to abolish them but to fulfil them.
 For truly, I say to you, till heaven and earth pass away, not an iota, not a dot, will pass from the law until all is accomplished.
 Whoever then relaxes one of the least of these commandments and teaches men so, shall be called least in the kingdom of heaven; but he who does them and teaches them shall be called great in the kingdom of heaven.
 For I tell you, unless your righteousness exceeds that of the scribes and Pharisees, you will never enter the kingdom of heaven.
 Then said Jesus to the crowds and to his disciples,
 "The scribes and the Pharisees sit on Moses' seat;
 so practice and observe whatever they tell you…"
And, of course, after saying that, Jesus went on to criticize the Pharisees severely. But that awareness of their faults didn’t stop him from instructing his disciples to “practice and observe whatever they tell you.”
So, Jesus kept the commandments and instructed his disciples to keep them.
Did they keep the commandments?
Yes, we have good reason to believe that they did. In Acts 21, we are told “And they [James and the elders] said to him, ‘You see, brother, how many thousands there are among the Jews of those who have believed; they are all zealous for the law…’” (Acts 21:20)
We learn from this passage not only that they kept the Law, but that there was no tradition of Jesus ever having abrogated the Law. These Christian Jews kept the Sabbath, did a ritual washing of hands before eating bread, and ate only kosher meat. Peter says explicitly that he ate only kosher meat.
 And I heard a voice saying to me, `Rise, Peter; kill and eat.'
 But I said, `No, Lord; for nothing common or unclean has ever entered my mouth.'
(Was Jesus telling him that he could eat unkosher meat? We’ll address that question in a second essay which will review the arguments against observing the commandments.)
Indeed, the doctrine of the Judaizers, that Jesus required not only Jewish but even Gentile Christians to keep the Law—makes no sense at all if Jesus himself had abrogated the observance of the Law. And notice that for all his opposition to the Judaizers, Paul never cites any teaching of Jesus to prove to argue his position.
Even when the Council of Jerusalem abrogated the observance of the Law by Gentiles, it retained certain prohibitions and, what is most noteworthy, it makes it clear that the decision was a concession to weakness, a pastoral rather than a doctrinal decision:
 Therefore I judge that we should not trouble those from among the Gentiles who are turning to God,
 but that we write to them to abstain from things polluted by idols, from sexual immorality, from things strangled, and from blood.
 For it has seemed good to the Holy Spirit and to us to lay upon you no greater burden than these necessary things:
 that you abstain from what has been sacrificed to idols and from blood and from what is strangled and from unchastity. If you keep yourselves from these, you will do well."
The decision of the Counsel of Jerusalem applied only to Gentiles. It was assumed that Jewish Christians would continue to keep the Law.
So we see that Jesus kept the Law, he required his disciples to keep the Law, and that, indeed, they did keep the Law and there was even a very strong movement to require all Christians to keep the Law.
The Christian faith of the Jewish believers in the Church of Jerusalem perfected their Jewish religious life. They felt no conflict between Jewish observance and Christian faith, for Jesus himself had enjoined them to keep the commandments and obey the teachings of the rabbis. Indeed, the teachings of Jesus enriched their experience of keeping the Law.
The Book of Acts gives us another Jewish witness to the perfect harmony of Jewish and Christian faith in the early Church. When Peter and the Apostles were brought before the high priest and his counsel, Rabbi Gamaliel spoke in their favor (Acts 5:34-39). Rabbi Gamaliel was the greatest rabbi of his generation. He is cited many times in the Talmud, and many of the greatest sages of the Talmud were his students. As you recall, Paul himself boasts of being his disciple (Acts 22:3) (though, with respect to the Christians, he certainly did not follow the example of his great teacher, for while Rabbi Gamaliel defended Peter and the apostles, Paul pursued and persecuted the Christian Jewish community). Rabbi Gamaliel makes a remarkably positive statement about Peter and the apostles before powerful men who hated the disciples of Jesus. He told them that the religious movement they represented might well be from G-d. And he warned them to let them alone, lest they “be found opposing G-d.” Rabbi Gamaliel would not have said that unless he know what they stood for and viewed it favorably—favorably enough to believe that it might just come from G-d. If there were anything in the teachings of Jesus or the apostles that even suggested the abrogation of the Law, he would not have said that about them. He probably wouldn’t have defended them at all.
 The God of our fathers raised Jesus whom you killed by hanging him on a tree.
 God exalted him at his right hand as Leader and Savior, to give repentance to Israel and forgiveness of sins.
 And we are witnesses to these things, and so is the Holy Spirit whom God has given to those who obey him."
 When they heard this they were enraged and wanted to kill them.
 But a Pharisee in the council named Gama'li-el, a teacher of the law, held in honor by all the people, stood up and ordered the men to be put outside for a while.
 And he said to them, "Men of Israel, take care what you do with these men.
 For before these days Theu'das arose, giving himself out to be somebody, and a number of men, about four hundred, joined him; but he was slain and all who followed him were dispersed and came to nothing.
 After him Judas the Galilean arose in the days of the census and drew away some of the people after him; he also perished, and all who followed him were scattered.
 So in the present case I tell you, keep away from these men and let them alone; for if this plan or this undertaking is of men, it will fail;
 but if it is of God, you will not be able to overthrow them. You might even be found opposing God!"
We have seen that the faith to which Jesus called the Jewish People was, indeed, a perfection of Jewish faith. His call was not to give up the commandments but to keep them with greater devotion and interiority. Jesus required his disciples to be more righteous than the Pharisees. What he meant was that, like the Pharisees, they should keep the Law, the Law as the Pharisees taught it, and then going beyond what they required, beyond the righteousness of the Pharisees, to keep the Law as an expression of an interior devotion to G-d. That, Jesus taught was the way of the Jew to the Kingdom of G-d.
But all that is history. Can a Catholic Jew practice the Law, believing himself obligated by G-d and, indeed, by Jesus himself, without stepping outside of the framework of Catholic faith and practice?
The Holy Father, while still a cardinal, provided us with an approach to the Law which suggests an emphatically affirmative answer to that question. Jesus, Cardinal Ratzinger writes, universalized the Law. In his recent book on Jesus, he is even more explicit: Christianity is the universalization of Judaism. What, then, is the Law? It is the particular way that Jews fulfill the Law of Christ—the Law as Jesus taught it. It is the Law of Christ as it was directed and addressed to the Jewish People.
“He [Jesus] lived his religious life within the framework of the faith and tradition of God’s People of Israel. His constant dialogue with the God of the Patriarchs, with his Father, was also a conversation with Moses and Elijah (cf. Mk 9:4). In this dialogue he passed beyond the letter of the Old Testament and laid bare its spirit in order to reveal the Father “in the Spirit”. In doing so, however, he did not destroy the letter of the Old Testament, i.e., the common religious tradition of Israel , but showed its real depth for the first time, “fulfilled” it. Thus, too, this dialogue did not destroy the idea of the “People of God”: it renewed it. Pulling down the wall of the letter resulted in giving the nations access to the Spirit of revelation and hence to God the Father, the God of Jesus Christ. This universalization of the tradition is its ultimate ratification, not its abrogation or replacement.” (Joseph Cardinal Ratzinger, Behold the Pierced One, Ignatius Press, 1986, p. 29)
This concept of the Law that is taught by the Holy Father is also suggested in the Catechism:
The Law of the Gospel fulfills the commandments of the Law. The Lord's Sermon on the Mount, far from abolishing or devaluing the moral prescriptions of the Old Law, releases their hidden potential and has new demands arise from them: it reveals their entire divine and human truth. It does not add new external precepts, but proceeds to reform the heart, the root of human acts, where man chooses between the pure and the impure, where faith, hope, and charity are formed and with them the other virtues. The Gospel thus brings the Law to its fullness through imitation of the perfection of the heavenly Father, through forgiveness of enemies and prayer for persecutors, in emulation of the divine generosity. (CCC 1968)
Just imagine how the observant Jew in the time of Jesus would have been inspired by his teachings. They introduced him to a whole new experience of the commandments. They added a whole new dimension to his Jewish religious life. Why, then, did the Church soon renounce the observance of the Law? Because the Church had to dissociate herself from the particular way that G-d had revealed the Law to the Jews in order to become a universal religion, a catholic Church. Once the Church took a stand against the practice of the Law, Christianity changed from being a religious movement that revitalized Jewish practice into a movement that, vis a vis Judaism, could only be viewed as heretical, for reverent devotion to the Law is the foundation of traditional Judaism.
In modern times, many Jews no longer keep the commandments. They have their reasons, arising largely out of the Reform and Conservative movements. Whatever they may be, they are not the reasons for the traditional teaching of the Church that the baptized Jew is no longer subject to Jewish Law. For the Church, the issue hinges on the relationship between the Old Covenant and the New, the Law of Moses and the Law of Christ. It is important to keep this in mind. The issue of Torah observance as it separates Orthodox from nonorthodox Jews is an entirely different matter. The purpose of this article was to show that on the basis of her own foundation documents, the Church has good reason for teaching that the New Covenant did not abrogate the Law.