My experience in the Jewish-Christian-Muslim trialogue took place mainly in the first decade of my work with the U.S. Conference of Catholic Bishops (USCCB). While the bishops had voted to establish a secretariat for interreligious affairs as well as one for ecumenical and Catholic-Jewish relations, they did not fund or provide staff for interreligious relations until the late 1980's, when Dr. John Borelli assumed the position. For the first ten years of the thirty I spent at the USCCB, I was asked to handle Catholic-Muslim as well as Catholic-Jewish relations, since it was felt that if I could handle two of the three Abrahamic traditions, I could at least adequately deal with the third, derived as it is from Judaism and Christianity, as one can tell from reading the Qur'an.
Before I discuss my experiences with the Abrahamic trialogue, a comment on the term may be in order. Critics of the term rightly note that "dialogue" does not simply mean words spoken between two people, but words spoken and received in such a way that the two individuals or groups involved are able to see into each other and understand how the other sees them and the world from, as it were, the inside. The word, the understanding of which we owe to the Jewish philosopher, Martin Buber, represents an "I-Thou" relationship as opposed to an instrumental "I-It" relationship, such as one might have with a store salesclerk, which is an "instrumental" rather than personal or soul-to-soul relationship. True dialogue, however, is "di" as in "diaphanous." The two see through and into each other. Critics of the term "trialogue" argue for the use of the term "trilateral dialogue" with regard to Jewish-Christian-Muslim relations. My own feeling, however, is that a different term than dialogue is helpful, since the relationship between Jews and Christians, on the one hand, and that of Jews and Christians with Muslims, on the other, is in fact qualitatively different.
Jews and Christians are bonded in covenant as, together, forming the People of God in a way distinct from their relationship with any other world religion, including Islam. The Jewish-Muslim relationship can be quite close and fruitful because of the similarity of their sacred tongues, the related Semitic languages of Arabic and Hebrew, and the fact that sharia (Muslim religious law) and halachah (Jewish religious law) share legal terms and concepts in common. But, Islam does not share sacred texts with either Jews or Christians in the way that Jews and Christians share the Hebrew Scriptures (to wrangle over and debate for their significance for our religious lives). Indeed, it is not accurate to call Jewish-Christian dialogue an "interfaith" dialogue at all. We claim as our own the faith of Abraham and Sarah, a share in God's enduring covenant with the Jews. Jesus was a Jew, faithful to God's Law as expressed to the Jewish People on Mt. Sinai and interpreted and reinterpreted in the subsequent books of what was, for Jesus, the Bible, the Hebrew Scriptures. He was killed by the Romans as a Jew. Christianity claims to be and is a renewed form of Judaism, not an entirely separate religion. Jewish-Christian relations can be called an "interreligious dialogue," since we are bound ("religio") to God by differing interpretations of the same scriptures, but not an "interfaith" dialogue, since we share essentially the same faith based upon the same scriptures, however differently interpreted.
Jews and Christians, however, cannot quite say the same thing in the same way regarding Muslim readings of the scriptures that we Jews and Christians share in common. Islam claims that, while the revelations to us may have been valid, Moses and Jesus being prophets in the line of prophecy sealed and ended by Muhammad, we Jews and Christians made mistakes in passing down the revelation in writing over the generations. Only the Qur'an is wholly accurate to God's revelation. So they do not regard either the Hebrew Scriptures or the Second Testament as sacred and binding upon them in the sense that both Jews and Christians regard and revere the Hebrew Scriptures. …