In the wake of the Holocaust, and with a growing understanding of how the traditional anti-Judaic teaching of the Church had rendered Christians all too vulnerable to the attacks against Jews by modern racial anti-Semitism, "Nostra Aetate" wisely went to the source of the problem in Christian teaching.
The problem was serious misunderstandings of the New Testament that began to infect the writings of the Fathers of the Church as early as the second century.
These misunderstandings revolved around the idea that the Jews as a people and all their descendants bore collective guilt for the death of Jesus. As "proof" the protagonists of this charge of "deicide" against the Jews would take various phrases from different Gospels and put them together to tell a "story" that none of the four evangelists would have recognized in their own versions of the Gospel.
The cry, "his blood be on us and on our children," for example, is recounted only in the Gospel of Matthew, but there it is the cry of a small "crowd" of people in Pilate's courtyard and not at all representative of the whole Jewish people.
But if one takes from the Gospel of John the phrase, "hoi 'Ioudaioi" -- "the Judeans" or "the Jews" -- which is a generalization used only in John, and attaches it to the Matthean text, as in "the Jews cried, 'His blood be upon us ...,'" one has an implication of collective guilt for Jesus' death not found in any of the Gospels, but only in the manipulation, conscious or unconscious, of the text.
Around this fundamental misunderstanding of the Gospel texts there arose over the centuries what has been called a "teaching of contempt" against Jews and Judaism -- for example, the notion that Jews were cursed by God for "their" crime, and suffered the destruction of the Jerusalem temple and perpetual wandering as divine punishment for it.
Interestingly, so pervasive was this negative teaching that no previous council of the Church had ever formally taken it up, though the Roman Catechism of the Council of Trent had argued that "our sins made the Lord Christ suffer" and that "our crime in this case is greater in us than in the Jews," since what the Jews of Jesus' time who were actually involved did was done in ignorance. "We [Christians], however, profess to know him, and when we deny him by our deeds, we seem in some way to lay violent hands on him," says the Roman Catechism 1, 5, 11.
The Second Vatican Council restated this ancient but obscured tenet of our faith in entirely unambiguous fashion, stating that one cannot blame all the Jews of Jesus' time "nor Jews today" for Jesus' death, and adding that "the Jews must not be spoken of as rejected by God or accursed," as if this followed from sacred Scripture. The council then formally rejected any form of anti-Semitism as contrary to the spirit of Christ.
While rejecting definitively the negative teachings against Jews and Judaism of the past, the Second Vatican Council simultaneously laid the doctrinal groundwork for an entirely positive theological appreciation of God's "irrevocable" covenant with the Jewish people, in our time no less than in biblical times.
It did this especially by recalling the positive implications of the New Testament text, Romans 9-11, that most thoroughly looks at the Mystery of Israel on its own terms after the time of Christ, translating in the present "theirs are the covenants and the promises," and calling on the Church to change its posture toward the Jews and Judaism from one of judgment into one which seeks a dialogue of "mutual esteem."
Worth reading in full.