Brandon points out in a comment to this post that I haven’t really defined what Williamson means by “anti-Judaism.” So here goes. First, it’s distinguishable from, though obviously related to, anti-Semitism. Anti-Judaism refers more broadly to the notion that Christianity is superior to, completes, and/or replaces Judaism as an ongoing religious enterprise. Williamson’s argument is that Christian doctrine and practice have been shaped, in pretty fundamental ways, by this binary view of Christianity: good/Judaism: bad.
Here are some quotes to fill out the details:
As Rosemary Ruether analyzes the anti-Jewish ideology of the church, it turns upon two major themes: rejection/election and inferiority/superiority. According to the first, in rejecting Jesus Christ the Jews are rejected by God, and in accepting Jesus Christ the Gentiles are elected. The price of the election of the Gentiles is the rejection of the Jews. Gentile believers displace them in the economy of salvation and in God’s favor. This motif pays a lot of attention to the “two peoples” allegory, the elder/younger brother stories in the Bible, and the claim that Jewish history is a “trail of crimes” culminating in deicide. According to the second theme, everything about Jewish faith and life is inferior to Christian faith and life, which is, in all respects, better. Christian ethics, worship, and biblical interpretation improve upon Jewish “law,” worship, and exegesis. The Christian way of doing things “fulfills” biblical promises, which Jews, being blind to the meaning of their own scriptures, misunderstand. Only Christians can rightly interpret the Hebrew Bible, which they make over into an “Old Testament.” Jews fail to recognize that their covenant has been superseded and continue to presume patently invalid modes of commitment to it. (Guest in the House of Israel, pp. 4-5)
David P. Efroymson’s somewhat different analysis looks upon anti-Judaism as a double-edged model, a model of and a model for. First, it is a model of Judaism, on which Judaism is a system and Jews a people “rejected by God, unfaithful to God, opposed to Christianity, and caught up in the crimes appropriate to their carnality, hardness, blindness, and vetustas [obdurate commitment to what is past and gone, oldness].” Jews are a people of oldness, Judaism a religion of oldness. On the same model, Christians, by contrast, are “a people and a system of newness, of fidelity, of spirituality, of moral vigor, and of universality.” At the same time, anti Judaism is a model for how Christians are to be Christians. It is [quoting Elfroymson]
a model for action, for acting “ethically,” for praying or worshiping “spiritually,” for reading the Bible accurately–all in specific and clearly focused distinction from the Jewish way of acting, praying, and of reading the Bible.
If we ask what Christianity is, the anti-Jewish answer is: everything new, good, spiritual, and universal that the old, bad, carnal, and ethnocentric Jews can never be. (p. 5)
This isn’t just being critical of Judaism, it’s defining essential features of Christianity in terms of its opposition to Judaism. As Williamson says:
Every Christian doctrine can be and was interpreted through the lens of this anti-Jewish hermeneutic. God is the God who displaces Jews and replaces them with Christians. Christ is the mediator on behalf of Christians who cuts a displacement deal with God. The church is the replacement people who displace Jews in the covenant. The covenant is a new covenant, replacing the old. The scriptures and their interpretation warrant these understandings. (p. 5)
Obviously, Williamson doesn’t think that Christianity is irredeemably anti-Jewish (he’s a Christian theologian, after all). What he’s contending is that anti-Judaism has been a pervasive influence on Christian teaching and practice for the better part of its history. And the result has been, directly, a distorted view of what Judaism is (Williamson points out that Judaism is just as capable of talking about God’s grace as Christianity is, for instance), and, indirectly, centuries of Christian persecution of Jews.