Millions of Christians across the world are observing Good Friday at the start of the Easter weekend when they believe Jesus Christ died and was resurrected.
Young and old come together for Good Friday in Sorrento, Italy
But ill-health means the Pope, who traditionally conducts Easter ceremonies, will not play a major role.
He appeared via video link at the Way of the Cross procession in Rome, sitting at his chapel in the Vatican.
The vicar of Rome read a message from the Pope, in which he said he was close to those who are tested by suffering.
"I also offer my suffering, so that God's design is completed and his word walks among the people," the message said.
Those taking part in the procession at the Colosseum waved torches and cheered as he appeared.
Acts of penitence
Good Friday has been marked in Asia with re-enactments of the crucifixion and sombre church ceremonies.
Crucifixion re-enactments draw big crowds in the Philippines
Devotees in the Philippines had their hands and feet nailed to large wooden crosses in a traditional imitation of the manner of Jesus' death.
Others marched through the streets whipping themselves with blades and chains in a show of penitence.
"This is just a little pain compared to my sins," Ruben Arriola, a house painter in the Filipino town of San Simon, told the Reuters news agency.
For many Christians, the past few days have been spent meeting relatives, shopping and preparing for the ceremonies this weekend.
Pope John Paul II has made two public appearances since leaving hospital last Sunday following throat surgery.
Recovery from the operation has been slower than expected, and his doctors have advised him not to attend the ceremony for the first time in his 26-year papacy.
A top cardinal, Joseph Ratzinger, told Italian television the Pope, though weakened, remained "lucid".
"And, given the physical trials John Paul II is going through, even this is a gift from God," the cardinal said.
The Pope, who is 84, is still expected to give his traditional Easter Sunday blessing.
He watched Holy Thursday services on television from his apartment.
"With mind and heart I am close to you," he said in a message read out on his behalf by a cardinal at an early evening service at St Peter's Basilica.
"Spiritually present, I pray with you, while with affection I bless all of you."
In another service earlier in the day, Cardinal Giovanni Battista Re, a senior Vatican official, paid tribute to the pontiff.
"We want to thank him for the witness he continues to give us even through his example of a serene abandonment to God, which he links to the mystery of the Cross," he said.
Orthodox Christians, who follow a different calendar, will celebrate Easter on 1 May.