NEW YORK (CNN) -- The sight was jarring Friday: Pope Benedict XVI at the Park East Synagogue just before the start of the Jewish Sabbath.
Pope Benedict XVI speaks Friday with Rabbi Arthur Schneier at the Park East Synagogue in New York.
It was the first time a pope had set foot inside a Jewish house of worship in the United States, a visit made at the invitation of Rabbi Arthur Schneier, who broke the silence in the synagogue by saying, "Your Holiness, a heartfelt shalom ... warm, warm welcome."
Benedict encouraged worshippers to "continue building bridges of friendship" with different ethnic and religious groups in their neighborhoods.
The invitation carried a significance rooted in the Holocaust, which affected both men profoundly. After his 14th birthday in 1941, Benedict -- then called Joseph Ratzinger -- was forced to join the Hitler Youth.
Schneier is a Holocaust survivor who was born in Vienna, Austria, and lived under the Nazis in Budapest, Hungary, during World War II. He came with his mother to the United States in 1947, determined to keep a promise he had made to his grandfather, also a rabbi, who did not escape the Nazis.
"He was always worried who's going to succeed him in his work, so I made a promise, which I've kept, to be ordained and devote my life to rabbinic service," Schneier said.
For more than 40 years, he has served as senior rabbi at the synagogue, where he has devoted his energies to fighting for religious freedom. In 2001, he was awarded the U.S. Presidential Citizens Medal.
Benedict has made other strides toward reaching out to Jewish leaders. As theological adviser to Pope John Paul II, he is credited with playing a key role in John Paul's decision to apologize to Jews for the role Catholics played in the Holocaust.
But Benedict has also angered Jews by reviving a controversial Latin prayer calling for their conversion, a move that did not please Schneier. "Would I wish that this prayer would not exist?" he asked. "Of course."
But the rabbi said he does not want to be paralyzed by the past and feels that it is his calling to do what he can to heal.
"The pope's visit here basically says to me, 'You know, you've embarked on the right road,' " the rabbi said. " 'Go forward; don't stop; continue.' "
The 78-year-old Holocaust survivor wished the pontiff "mazel tov" on his 81st birthday, which occurred two days ago. "The sun is shining, and the heavens are rejoicing on this day," Schneier said.
"I find it moving to recall that Jesus as a young boy heard the words of scripture and prayed in a place such as this," Benedict said. "I encourage all of you to continue building bridges of friendship." Watch the pope address Jewish worshippers »
Congregation members presented the pope with a Passover Seder plate, placed at the center of the dinner table during the holiday feast marking the occasion when Jews were led out of slavery in Egypt. He was also given a box of matzo and a Haggadah, the prayer book used during Passover.
In turn, the pope presented Schneier with a Jewish manuscript.
As the pope shook hands with invited congregation members, they sang "Oseh Shalom," a song and prayer for peace.
Friday's event took place a day after Benedict met in Washington with religious leaders from different faiths, stood on a temple stage and watched as the ark was opened to reveal the Torah scrolls, the first five books of the Hebrew Scriptures.
The event symbolized the Catholic church's efforts to improve interfaith relations.
Benedict's three-day visit to New York is the second leg of his six-day trip to the United States, his first since he was elected to the papacy.
After Park East Synagogue, he traveled to St. Joseph's Parish for a prayer service.
On Saturday he is to celebrate Mass at St. Patrick's Cathedral on Fifth Avenue and visit the World Trade Center ground zero ahead of celebrating Mass at Yankee Stadium.
On Friday morning, the pope addressed the U.N. General Assembly and urged the members to intervene in nations unable to protect their populations from human rights violations.
"Every state has the primary duty to protect its own population from grave and sustained violations of human rights, as well as from the consequences of humanitarian crises, whether natural or man-made," he said.
"If states are unable to guarantee such protection, the international community must intervene," he said in French, citing the United Nations Charter and in other international instruments.
Later, switching to English, he said, "The promotion of human rights remains the most effective strategy for eliminating inequalities between countries and social groups, and for increasing security."
He was referring to the Universal Declaration of Human Rights, which the United Nations adopted December 10, 1948.
"As history proceeds, new situations arise, and the attempt is made to link them to new rights," he said.
"Discernment -- that is, the capacity to distinguish good from evil -- becomes even more essential in the context of demands that concern the very lives and conduct of persons, communities and peoples."
Benedict was the third pope to address the General Assembly. Pope Paul VI visited in 1965, and Pope John Paul II visited in 1979 and 1995.
The pope expressed admiration for the U.N.'s mission, saying its founding principles -- "the desire for peace, the sense of justice, respect for the dignity of the person, humanitarian cooperation and assistance -- express the just aspirations of the human spirit and constitute the ideals which should underpin international relations."
However, he conveyed concern that the international body's decisions were made by only a small number of nations.
"Multilateral consensus ... continues to be in crisis because it is still subordinated to the decisions of a few, whereas the world's problems call for interventions in the form of collective action by the international community," he said. E-mail to a friend
CNN correspondents Steve Kastenbaum and Mary Snow contributed to this report.