VATICAN CITY -- Returning to the world's most storied pulpit for the first time since his hospitalization, Pope John Paul II addressed a sea of worshipers yesterday from his studio on St. Peter's Square and gave with his presence what no cardinal's words could deliver: a strong assurance that he is on the rebound.
An aide delivered most of the message, but at the end the pope's voice rang out clearly: ''Happy Sunday to everybody. Thank you."
The 84-year-old pontiff looked alert as he waved to the crowd with a trembling hand. He gave a brief greeting before Archbishop Leonardo Sandri of Argentina carried on with the address. Thousands of pilgrims applauded, and some shouted ''Viva il Papa!" -- ''Long live the pope!"
''We meet again in this place to praise the Lord," the pope said in his message, read by the bishop.
The pope was rushed to a Rome hospital Feb. 1 with breathing difficulties after coming down with the flu. He returned to the Vatican on Thursday.
In a subtle rebuttal to rumors the pope might step down because of frail health, the bishop read on the pope's behalf a message saying: ''I always need your help before the Lord, for carrying out my mission that Jesus entrusted to me."
The pope's appearance at St. Peter's is a cherished Sunday tradition for Roman Catholics, and its resumption was expected to come as a relief for believers around the world. Thousands of people packed the square to catch a glimpse of the pontiff.
''I thought he was amazing, given his age," said Catherine Kelly, of Newcastle, England.
Although the pope's voice was weak, ''it was nice to hear him," said Terry Elsdon, Kelly's brother.
The pope's message included an appeal for hostages in Iraq, including kidnapped Italian journalist Giuliana Sgrena. The pope's return to the Vatican coincided with his weeklong spiritual retreat beginning yesterday, scheduled before he fell ill. During that period all audiences will be suspended, including the pontiff's customary Wednesday public audience.