Christians Worldwide Celebrate Easter

Orthodox Christians gather for an Easter Mass at Sioni Cathedral in Tbilisi.

Millions of Christians worldwide are celebrating Easter, one of the most important holidays on the Christian calendar.

Easter Sunday celebrates the resurrection of Jesus, which his followers believe occurred on the third day after his death by crucifixion some time around A.D. 30.

This year, Christianity's main branches - Protestantism, Catholicism, and Eastern Orthodoxy -- celebrate Easter on the same day. That only happens about once every two or three years, depending on a complex calculation derived from different calendars used by the Western and Eastern churches.

For many, Easter is a chance to heal wounds -- and seek peace.

In Moscow, Russian President Dmitry Medvedev and Prime Minister Vladimir Putin attended an overnight service at the Christ the Savior Cathedral.

Thousands of worshippers gathered for the ceremony, led by Russian Orthodox Patriarch Kirill, amid tight security.

The Orthodox Easter celebrations came amid a recent tide of violence in Russia. On March 29, two suicide bombers killed 40 people on the Moscow metro. Two days later, twin suicide bombings killed 12 people in the North Caucasus republic of Daghestan, and today a bombing in the republic derailed a freight train.

In his Easter address, Medvedev noted the symbolism of the fact that this year Christians of all denominations celebrate Easter on the same day. He said their cooperation for peace and mutual understanding would contribute to more harmonious interethnic and interconfessional relations.

In his message, Putin congratulated Patriarch Kirill for the "enormous" role the Orthodox Church had played in the "renaissance of national traditions and the consolidation of society." He expressed hope that Easter would "bring peace and love into every home."

In the United States, President Barack Obama called on people of all faiths to embrace their common aspirations and "shared spirit of humanity."

And at St. Peter's Basilica in the Vatican, Pope Benedict XVI delivered the traditional “Urbi et Orbi” blessing, "for the city and the world."

The Catholic Church has been engulfed in widespread accusations of child abuse committed by clergy and hidden by the institution. In a reference to the scandal, a senior cardinal, Angelo Sodano, told the 82-year-old pope at the beginning of the mass: “The people of God are with you and will not let themselves be influenced by the petty gossip of the moment, by the trials that sometimes assail the community of believers.”

The pontiff himself has been accused of failing to take action against a suspected abuser during his tenure as archbishop of Munich, a claim the Vatican denies.

Some Catholic leaders have defended the Pope against what they describe as defamatory attacks by the media. But senior clerical figures have called on the Church to be more transparent.

In his "Urbi et Orbi" message, the pontiff made no apparent reference to the scandal, but said Easter brings a message of pardon, goodness, and truth to a suffering world.

Pope Benedict also urged mankind to undergo a "spiritual and moral conversion." He offered prayers for the "suffering" Christian communities in Iraq and expressed fear for Christians suffering "persecution and even death" in Pakistan.