Nostra Aetate (Latin for "In Our Times") was written during he Second Vatican Council, a landmark meeting of Catholic clergy that many theologians credit with updating church teachings. Issued on October 28, 1965, the historic document outlines the Catholic Church's relationship with non-Christian religions, specifically Hinduism, Islam and Judaism.
"A real transformation has taken place in these 50 years in the relationship between Christians and Jews," the Pope said in a speech in Rome on Wednesday. "From enemies and strangers, we have become friends," he said.
Before 1965, the Catholic Church considered the Jewish people responsible for the death of Jesus.
"True, the Jewish authorities and those who followed their lead pressed for the death of Christ; still, what happened in His passion cannot be charged against all the Jews, without distinction, then alive, nor against the Jews of today."
Before 1965, Catholics prayed for Jews in this way:
"Let us pray also for the faithless Jews: that almighty God may remove the veil from their hearts; so that they too may acknowledge Jesus Christ our Lord."
After Nostra Aetate, the prayer reads:
"Let us pray also for the Jewish people, to whom the Lord our God spoke first, that he may grant them to advance in love of his name and in faithfulness to his covenant."
Francis on Wednesday also recalled that Nostra Aetate definitively rejected all forms of anti-Semitism, saying " 'no' to every form of anti-Semitism and condemnation of every injury, discrimination and persecution that derives from it."
The Pope also mentioned the Catholic Church's esteem for Muslims, as expressed in Nostra Aetate in 1965.
"Violence and terrorism have caused a widespread attitude of suspicion or even condemnation of religions," Francis said Wednesday.
"In reality, given that no religion is immune from the risk of fundamentalist or extremist deviations by individuals or groups, it is important to look at the positive values which they live and propose," he said.
Francis called on believers from all religions, as well as nonbelievers, to collaborate on issues that plague the world today, from hunger to corruption to environmental degradation.
"We believers do not have recipes for these problems," he said, "but we have a great resource: prayer."
"We should always leave the world better than we found it," the Pope said, "starting with the environment in which we live, in the little gestures of our daily lives."
Attacks on Israel
Meantime, a Jewish leader said he met with the Pope on Wednesday and asked him about people who said they were not anti-Semitic, "just anti-Israel."
Ronald Lauder, the president of the World Jewish Congress, quoted the Pope as replying: "To attack Jews is anti-Semitism, but also an outright attack on the State of Israel is anti-Semitism. There may be political disagreements between governments on political issues, but the State of Israel has every right to exist in safety and prosperity."
Vatican spokesman Federico Lombardi did not immediately respond to a CNN request to confirm the comments, but a senior Vatican source said the reported remarks were consistent with the Holy See's position on Israel. The source said he could not confirm that the Pope had made the remarks because he was not at the private meeting.