Battling age and illness, Pope John Paul II has celebrated an open-air Mass at the Roman Catholic shrine in Lourdes, south-western France.
The pilgrimage marks the 104th foreign trip of this papacy
Some 200,000 people attended the Mass by the grotto revered for its healing powers, cheering the Pope through his sermon with cries of "Viva Il Papa".
The pontiff had to stop to ask an aide for water, saying "Help me", then insisting: "I have to finish".
It was the second pilgrimage to Lourdes for the 84-year-old Church leader.
Speaking in 30C (86F) heat at the Grotto of St Bernadette, which is dedicated to the Virgin Mary, the Pope made a strong appeal against abortion and euthanasia.
He drew applause from the congregation standing in a meadow under the basilica which now covers the cave, with some people moved to tears.
"I'm not here looking for a miracle," Christopher Weeratunde, a 66-year-old Briton, told Reuters news agency from his wheelchair.
"I'm here to share my faith and my suffering with the Pope. My whole purpose today is
to be near him. This is the greatest day of my life."
The BBC's David Willey says that although the Pope's actual words are often incomprehensible these days because of the progression of Parkinson's Disease, the power of his presence remains undiminished.
For the vast majority of Catholics, our Rome correspondent reports, he has become an icon of suffering humanity.
The pontiff managed a smile for the pilgrims
The image is particularly poignant in Lourdes where people are welcomed as they drink or bathe in spring water which they believe has healing powers.
The larger question being asked in Rome, of how long the Catholic Church can go on being governed by a Pope in seriously failing health, seemed of little relevance at Sunday's Mass, our correspondent adds.
The service, dedicated to the Feast of the Assumption, was the main event on the Pope's two-day pilgrimage.
The Feast celebrates the ascent into heaven of Mary, mother of Jesus Christ.
Our correspondent says the Pope has a strong personal devotion to Mary, whom he believes saved his life when he was hit by a would-be assassin's bullet two decades ago.
'A time of suffering'
The Pope headed for Rome after the visit, which began on Saturday, when the pontiff prayed in the grotto, making a rare personal reference to his own declining health.
"With you I share a time of life marked by physical suffering, yet not for that reason any less fruitful in God's wondrous plan," he said in a statement to fellow pilgrims, which a French cardinal read out for him.
Six million pilgrims, many of them very sick, come to seek healing and to worship at the shrine each year.
It was in Lourdes that a 14-year-old French girl, Bernadette Soubirous, claimed to have witnessed a series of visions of the Virgin Mary in a cave in the mid-19th Century.