Comparing Christianity & Judaism


Kreeft outlines the main theological and practical differences, as well as the important common elements, between Christianity and Judaism.

If Jesus returned to earth today, which church would He go to? A Catholic church, of course, replies the Catholic. No, a Protestant church, argues the Protestant. I think both are wrong. I think he would begin as He did 2,000 years ago in a Jewish synagogue.

The long history of Christian anti-Semitism, in thought and deed, is perhaps the worst scandal in all the Church's history. It is the Oedipus complex, for Judaism is Christianity's father. All Christians are spiritually Jews, said Vatican II, echoing St. Paul. Christianity subtracts nothing from Judaism, but only fulfills it.

This is the point of the “Jews for Jesus,” who insist that a Jew who becomes a Christian does not lose anything Jewish but completes his or her identity. When a Hindu or a pagan becomes a Christian, he is converted. When a Jew becomes a Christian, he is completed.

This is surely Jesus' point of view too, for He said He came not to destroy the Law and the Prophets but to fulfill them. From His point of view, Christianity is more Jewish than modern Judaism. Pre-Christian Judaism is like a virgin: post-Christian Judaism is like a spinster. In Christ, God consummates the marriage to His people and through them to the world.

What have Christians inherited from the Jews? Everything in the Old Testament. The knowledge of the true God. Comparing that with all the other religions of the ancient world, six crucial, distinctive teachings stand out: monotheism, creation, law, redemption, sin and faith.

Only rarely did a few gentiles like Socrates and Akenaton ever reach to the heights and simplicity of monotheism. A world of many forces seemed to most pagans to point to many gods. A world of good and evil seemed to indicate good and evil gods. Polytheism seems eminently reasonable; in fact, I wonder why it is not much more popular today.

There are only two possible explanations for the Jews' unique idea of a single, all-powerful and all-good God: Either they were the most brilliant philosophers in the world, or else they were “the Chosen People” — i.e., God told them. The latter explanation, which is their traditional claim, is just the opposite of arrogant. It is the humblest possible interpretation of the data.

With a unique idea of God came the unique idea of creation of the universe out of nothing. The so-called “creation myths” of other religions are really only formation myths, for their gods always fashion the world out of some pre-existing stuff, some primal glop the gods were stuck with and on which you can blame things: matter, fate, darkness, etc. But a Jew can't blame evil on matter, for God created it; nor on God, since He is all-good. The idea of human free will, therefore, as the only possible origin of evil, is correlative to the idea of creation.

The Hebrew word “to create” (bara) is used only three times in the Genesis account: for the creation of the universe (1:1), life (1:21) and man (1:27). Everything else was not “created” (out of nothing) but “formed” (out of something).

The consequences of the idea of creation are immense. A world created by God is real, not a dream either of God or of man. And that world is rational. Finally, it is good. Christianity is a realistic, rational and world-affirming religion, rather than a mythical, mystical, or world-denying religion because of its Jewish source.

The essence of Judaism, which is above all a practical religion, is the Law. The Law binds the human will to the divine will. For the God of the Jews is not just a Being or a Force, or even just a Mind, but a Will and a person. His will is that our will should conform to His: “Be holy, for I am holy” (Lev. 11:44).

The Law has levels of intimacy ranging from the multifarious external civil and ceremonial laws, through the Ten Commandments of the moral law, to the single heart of the Law. This is expressed in the central prayer of Judaism, the shma (from its first word, “hear”): “Hear O Israel: the Lord, the Lord our God is one Lord; and you shall love the Lord your God with all your heart and with all your soul and with all your might” Deut. 6:4).

Thus, the essence of Judaism is the same as the essence of Christianity: the love of God. Only the way of fulfilling that essence — Christ — is different. Judaism knows the Truth and the Life, but not the Way. As the song says: “Two out of three ain't bad.”

Even the Way is foreshadowed in Judaism, of course. The act brought dramatically before the Jews every time they worshiped in the temple was an act of sacrifice, the blood of bulls and goats and lambs foretelling forgiveness. To Christians, every detail of Old Testament Judaism was a line or a dot in the portrait of Christ. That is why it was so tragic and ironic that “He came to what was His own, but his own people did not accept Him” (John 1:11). Scripture is His picture, but most Jews preferred the picture to the person.

Thus the irony of His Saying:

You search the Scriptures, because you think you have eternal life through them; even they testify on my behalf” (John 5:39-40).

No religion outside Judaism and Christianity ever knew of such an intimate relationship with God as “faith.” Faith means not just belief but fidelity to the covenant, like a marriage covenant. Sin is the opposite of faith, for sin means not just vice but divorce, breaking the covenant.

In Judaism, as in Christianity, sin is not just moral and faith is not just intellectual; both are spiritual, i.e., from the heart. Rabbi Martin Buber's little classic “I and Thou” lays bare the essence of Judaism and of its essential oneness with Christianity.

Christians are often asked by Jews to agree not to “proselytize.” They cannot comply, of course, since their Lord has commanded them otherwise (Matt. 28:18-20). But the request is understandable, for Judaism does not proselytize. Originally this was because Jews believed that only when the Messiah came was the Jewish revelation to spread to the gentiles. Orthodox Jews still believe this, but modern Judaism does not proselytize for other reasons, often relativistic ones.

Christianity and Judaism are both closer and farther apart than any two other religions. On the one hand, Christians are completed Jews; but on the other, while dialogue between any two other religions may always fall back on the idea that they do not really contradict each other because they are talking about different things, Jews and Christians both know who Jesus is, and fundamentally differ about who He is. He is the stumbling stone (Is. 8:14).


Kreeft, Peter. “Comparing Christianity & Judaism.” National Catholic Register. (May, 1987).

Reprinted by permission of the author. To subscribe to the National Catholic Register call 1-800-421-3230.


Peter Kreeft has written extensively (over 25 books) in the areas of Christian apologetics. Link to all of Peter Kreeft's bookshere.

Peter Kreeft teaches at Boston College in Boston Massachusetts. He is on the Advisory Board of the Catholic Educator's Resource Center.

Copyright © 1987 National Catholic Register