Pope Francis offered a message of religious tolerance and compassion during his trip to Jewish and Muslim holy sites in Israel on Monday.

Pope Francis urged "mercy, magnanimity and compassion" while visiting the Yad Vashem Holocaust memorial museum. He called the Holocaust a "boundless tragedy," and called for an end to anti-Semitism, The Boston Globe reports.

On Monday, Francis also visited Dome of the Rock, the site where Muslims believe Muhammad went to heaven, and the Western Wall, the last portion of the ancient Israelite temple that is considered the holiest Jewish site. The pope also met with both Muslim and Jewish leaders, and was accompanied by his inter-religious partners, Rabbi Abraham Skorka and Muslim leader Omar Abboud.

At Dome of the Rock, Francis addressed Grand Mufti Muhammad Ahmad Hussein and other Islamic leaders, expressing his happiness at being with his "dear Muslim friends." He also urged Christians and Muslims to work together for "peace and justice."

In an inferred reference to terrorism and other forms of religious violence, he made a plea that "no one abuse the name of God through violence."

The pontiff was then greeted by a small Jewish delegation at the Western Wall, who explained the site's history. He then approached the wall for moments of silent prayer.

Pope Francis also followed the tradition of placing notes for God in the wall's crevices. He placed a handwritten note of a Christian prayer, written in Spanish, to reference the unity of the religions.

He told the rabbis at the wall that he is happy to be with Christianity's "older brothers."

He said that there should be more social ties between Judaism and Christianity, as well as a acknowledgement of the "spiritual significance of the bond existing between us."

He then called on all faiths to "firmly oppose every form of anti-Semitism and all other forms of discrimination."

Pope Francis was also the first pope to a lay a wreath at the tomb of Theodor Herzl, the founder of Zionism who is considered to be the father of the state of Israel.

The pope also visited Yad Vashem, where he met with a small group of Holocaust survivors. He kissed the hands of the survivors and listened to their stories.

Joseph Gottdenker, who was born in Poland in 1942 to a Jewish family and raised in hiding by Catholics, was surprised by the pope kissing his hand.

"I didn't know it was going to happen," he said. "I thought I should be kissing his hand, not the other way around."

Pope Francis then quoted the Torah, the Jewish Bible, and commented that the Holocaust was an evil so immense that "perhaps not even the Father could imagine so great a fall, so profound an abyss."

Yet, despite the pope's calls for unity, peace and understanding, there were moments during the trip when the political tension in the region came to the fore.

An Israeli foreign ministry spokesman called the pope's unscheduled prayer at the barrier between Israel and the West Bank a "propaganda stunt," and Grand Mufti Hussein called Israel an "occupation" of Palestinian territory.

"We demand justice and to put an end to the Israeli occupation that seeks to cancel our identity," Hussein said.

Pope Francis will also celebrate a Mass in the Cenacle, the place where Christians believe Jesus had the last supper and where Jews believe King David's tomb is located.

Ultra-Orthodox Jews are angered by the pope holding mass in the holy site. Police arrested 26 ultra-Orthodox demonstrators after more than 150 activists tried to storm the complex.

After the mass, the Pope will make a return flight to Rome.