A white canopy on the steps of St. Peter's Basilica protected the 80-year-old pontiff from the chilly rain, while thousands of pilgrims, tourists and Romans huddled under a sea of colored umbrellas in the square.
The crowd was expected to grow before the noon Urbi et Orbi (Latin for "to the city and to the world") address, which has previously been an occasion for pontiffs to speak about the globe's conflicts and other problems.
Just before the late morning Mass began, a thunderclap competed with a chorus of "Alleluia," and the already gray sky grew darker.
A rainstorm forced the pope to skip walking in the Way of the Cross Good Friday procession at the Colosseum.
Christians on Easter celebrate their belief in the resurrection of Jesus two days after he was crucified.
Benedict told the faithful in the square that the resurrection "broke the chains of death" and that thanks to the apostles' preaching, "thousands and thousands of persons converted to Christianity."
"And this is a miracle which renews itself even today," the pope said at the start of the Easter Day Mass.
Allam, 55, is deputy editor of Corriere della Sera newspaper and writes often on Muslim and Arab affairs. He was born a Muslim in Egypt, but was educated by Catholics and says he has never been a practicing Muslim.
Saying he was writing as a "private citizen," Allam said in a letter published Sunday in Corriere that he was now taking on a middle name, "Cristiano," (Christian in Italian). "From now on, I will call myself Magdi Cristiano Allam," he wrote, expressing gratitude to Benedict.
The day of his baptism was "the most beautiful day of my life," Allam wrote.
"The miracle of the resurrection of Christ reverberated in my soul, freeing it from the shadows of a preaching where hate and intolerance toward he who is different, toward he who is condemned as an 'enemy,' prevailed over love and respect for your neighbor."
Allam's criticism of Palestinian suicide bombings prompted the Italian government to provide him with a sizable security detail in 2003, after Hamas singled him out for death, Allam told the Il Giornale newspaper in a December interview.
The pope himself has come under verbal attack from Islamic militants.
Osama bin Laden, in a new audio message posted last week, accused Benedict of playing a role in what he called a "new Crusade" against Islam. The Vatican has described the accusation as baseless.
Security during papal public appearances was stepped up in 2001 after the Sept. 11 attacks, and there has been no noticeable increase in protective measures since the new message surfaced.
Christians Gather In Jerusalem To Mark Easter Sunday
Pilgrims thronged Christian holy sites in Jerusalem on Sunday, braving a heightened security alert to celebrate Easter in the city where they believe Jesus was resurrected on this day two millennia ago.
In the walled Old City, hundreds of believers escaped the stifling temperatures of an unseasonable heat wave and filled the cool, dark rooms of the Church of the Holy Sepulcher, traditionally the site where Jesus was crucified, buried and resurrected. The odor of incense wafted from the church doors into the courtyard outside.
Ahead of the weekend, security forces deployed thousands of officers nationwide to secure events connected with Easter and the Jewish festival of Purim. The alert was also high because of Israeli concerns about a possible revenge attack for the assassination of a Hezbollah commander last month in Syria.
Israel denied involvement, but Hezbollah has blamed the Jewish state and threatened to avenge his death with an attack on Israeli targets.
On March 6, a Palestinian gunman killed eight young students at a Jerusalem rabbinical seminary, the first major attack in the city in four years.
Jeri Minasy, 59, a retired flight attendant from Newnan, Georgia, said the recent violence couldn't deter her from spending Easter in Jerusalem. She called the experience "special, mystic and spiritual."
But she wondered what Jesus would think about the bloodshed. "I think he would be appalled that people can't get along. He would be crying," Minasy said.
The Roman Catholic Church's leader in the Holy Land, Latin Patriarch Michel Sabbah, led a procession of clergymen through the church. Wearing white-and-gold robes and holding a silver staff, Sabbah chanted hymns in Latin as he circled the structure.
Tamera Perry, 39, a high school teacher from Silver City, New Mexico, said she planned to videotape the Easter Mass and send it over the Internet to her church at home, where it would be shown on a projector at the Easter service.
She hoped to transmit something of the experience of being in Jerusalem for the holiday, Perry said.
"I get a real sense of the surroundings here, being where Jesus walked and walking the hills that he walked," she said.
Not all believers chose to mark Easter at the Holy Sepulcher. Some Protestants venerate a spot outside the Old City known as the Garden Tomb as the site of Jesus' burial, and groups gathered there early Sunday to sing songs accompanied by a rock band. Some raised their hands and swayed to the music.
"We can say that resurrection day was the happiest day in history," Peter Wells, the site's chaplain, told the crowd, speaking at a podium bearing the words, "Jesus Is Alive."
"So once again, the Lord is risen," Wells said, and the assembled believers answered in unison: "The Lord is risen indeed, hallelujah!"
U.S. Vice President Dick Cheney, who was in Jerusalem on Sunday, marked Easter with a service at the U.S. consulate before setting out for a day of meetings with Israeli and Palestinian leaders.
Suicide Bomb Kills 13 Iraqi Soldiers; U.S.-Protected Green Zone Comes Under Fire
A suicide car bomber killed at least 13 Iraqi soldiers and wounded dozens more people in Iraq's north on Sunday. Meanwhile, the U.S.-protected Green Zone in Baghdad came under fire from either mortars or rockets, and a round that fell short injured two bystanders.
The Easter Sunday attacks underscored the fragility of Iraq's security, despite a decline in violence over the past year. They also came as the U.S. military death toll in Iraq nears 4,000.
Iraqi security forces opened fire on the bomber as he drove toward the military base in the northwestern city of Mosul but were unable to foil the attack because the truck's windshield had been made bullet-proof.
The attacker blasted through an armored vehicle to reach the courtyard of the military headquarters, according to an Iraqi army officer, who spoke on condition of anonymity because he wasn't authorized to release the information.
Police said at least 13 Iraqi soldiers were killed and 42 people wounded - 30 soldiers and 12 civilians - in the attack. Mosul, 225 miles northwest of Baghdad, has been described by the U.S. as the last urban stronghold of the Sunni-led al Qaeda in Iraq.
Shiite extremists were suspected to be behind the barrages against the Green Zone, which houses the U.S. and British embassies and the Iraqi government headquarters.
About 10 detonations were heard starting shortly before 6 a.m in the sprawling area in central Baghdad. Several other mortars or rockets slammed into the area about four hours later.
The U.S. public address system in the Green Zone warned people to "duck and cover" and to stay away from windows following both attacks.
No casualties were reported inside the Green Zone, a frequent target of rocket and mortar attacks that is located on the west bank of the Tigris River. But one round fell short and exploded in a major traffic circle on the east side of the river, injuring two people nearby, police said.
There were no claims of responsibility for the barrages, but it appeared the rounds were fired from areas of eastern Baghdad where the biggest Shiite militia, the Mahdi Army of radical cleric Muqtada al-Sadr, operates.
A cease-fire called by al-Sadr, along with an increase in U.S. troop levels and a move by American-backed Sunni fighters to turn against their former al Qaeda in Iraq allies, have been credited with sharply reducing violence in Baghdad and surrounding areas.
But there are fears that the cease-fire may unravel after a series of clashes between U.S.-Iraqi forces and Shiite militiamen in Baghdad, Kut and other areas south of the capital.
In other violence Sunday, a blast killed eight, including two women and two children, in southeastern Baghdad, police said. The cause of the explosion was not immediately known.
On Saturday, U.S. officials said three American soldiers were killed in a roadside bombing that also killed two Iraqi civilians northwest of Baghdad. The latest deaths brought to 3,996 the number of U.S. service members and Pentagon civilians who have died since the war began on March 20, 2003, according to an Associated Press count.
A suicide bomber late Saturday also drove a truck laden with explosives into the home of the mayor in Samarra, 60 miles north of Baghdad. Three security guards were killed and four others injured, police said.