Pope Francis kisses a baby after celebrating his first Easter Mass on Sunday in St. Peter's Square at the Vatican. Pope Francis celebrated his first Easter Mass as pontiff in St. Peter's Square, packed by joyous pilgrims, tourists and Romans and bedecked by spring flowers.

VATICAN CITY — Pope Francis marked Christianity’s most joyous day with a passionate plea for world peace, celebrating his first Easter Sunday as pontiff in the enthusiastic company of more than 250,000 people who overflowed from St. Peter’s Square.

With eloquent words in his Easter message, Francis lamented enduring conflicts in the Middle East, on the Korean peninsula and elsewhere and remembered the world’s neediest people. With physical gestures, he illustrated the personal, down-to-earth caring he brings as a pastor to this new papacy — cradling a disabled child held out to him in the crowd and delightedly accepting a surprise gift thrust at him.

Francis shared in his flock’s exuberance as they celebrated Christianity’s core belief that Jesus Christ rose from the dead following crucifixion. After Mass in flower-bedecked St. Peter’s Square, he stepped aboard an open-topped white popemobile for a cheerful spin through pathways in the joyous crowd, kissing babies, smiling constantly and patting children on the head.

One admirer of both the pope and his favorite soccer team from his Argentine homeland, Saints of San Lorenzo, insisted that Francis take a team jersey he was waving at the pontiff — “take it, go ahead, take it,” the man seemed to be telling the pope. Finally, a delighted Francis obliged, briefly holding up the shirt, and the crowd roared in approval. He handed the shirt to an aide in the front seat, and the popemobile continued its whirl through the square.

In a poignant moment, Francis cradled and kissed a physically disabled boy passed to him. The child worked hard to make one of his arms hug the pope back, then succeeded, smiling in satisfaction as the pope patiently waited for the boy to give his greeting.

Francis has repeatedly put concern for the poor and suffering at the center of his messages, and he pursued his promotion of the causes of peace and social justice in the Easter speech he delivered from the central balcony of St. Peter’s Basilica, the same vantage point above the square where he was introduced to the world as the first Latin American pope on March 13.

The Roman Catholic leader aimed his Easter greetings at “every house and every family, especially where the suffering is greatest, in hospitals, in prisons.” Francis prayed that Jesus would inspire people to “change hatred into love, vengeance into forgiveness, war into peace.”