Pope Francis is calling on humanity to not let sadness prevail because of the many forms of violence afflicting the world.

Francis cited no specific violent event in his homily Sunday in a Rome basilica, St. John in Lateran. But he said: "We can't let ourselves be overcome by weariness. No form of sadness is allowed, even if we would have reason to, because of the many worries and multiple forms of violence which wound our humanity."

The ceremony was part of the special church Holy Year highlighting his emphasis on the importance of mercy and pardon.

After opening a symbolic Holy Door in the ancient cathedral, Francis told the faithful that "God doesn't love rigidity" but is tender.