Pope Benedict told religious leaders, including Christians, Jews and Muslims, today that faith must never be allowed to become a vehicle of hatred.
The Pope spoke forcefully against invoking the name of God in any religion "to justify evil and violence".
"Faced with a world lacerated by conflict, where violence is still justified in the name of God, it is important to reiterate that religions must never become a vehicle of hatred," the Pontiff said.
"On the contrary, religions can and should offer precious resources to build a humanity of peace, because they speak of peace at the heart of man."
The Pope addressed scholars and religious leaders attending a three-day inter-faith gathering in the southern Italian port city of Naples. The conference is called "For a World Without Violence: Religions and Cultures in Dialogue".
Less than two weeks ago more than 130 Muslim scholars called for peace and understanding between Islam and Christianity, and said the world's survival could be at stake.
The Pope sat down to lunch on Sunday with one of them, Izzeddin Ibrahim, a cultural adviser to the government of the United Arab Emirates.
"With respect for the differences between different religions, we are all called to work for peace and an effective effort to promote reconciliation between peoples," the Pope said.
The Pope also met religious leaders including Israel's Chief Rabbi Yona Metzger, the spiritual head of Orthodox Christians, Ecumenical Patriarch Bartholomew and the Archbishop of Canterbury Rowan Williams, the head of the world's Anglicans.
"I strongly hope that this spirit (of peace) spreads above all where tensions are strongest, where freedom and the respect for others are denied, and men and women suffer because of the consequences of intolerance," he said.
Muslim leaders attending the summit included Din Syamsuddin, the head of Indonesia's second largest Islamic organisation - the 30 million-member Muhammadiyah.
He was one of the many Muslims who criticised a speech the Pope made last year hinting Islam was violent and irrational. Benedict repeatedly expressed regret for the reaction to the speech, but stopped short of a clear apology sought by Muslims.
During the inter-religious talks, the Vatican expressed joy over the release of two Catholic priests. They were kidnapped in the northern Iraqi city of Mosul this month and there were reports they were being held for a $1 million ransom.