Pope Francis washed the feet of 12 young offenders including two girls at a Rome prison on Thursday in an unprecedented version of an ancient Easter ritual seen as part of an effort by the new pope to bring the Catholic Church closer to the needy.
"Whoever is the most high up must be at the service of others," the pope said at the start of the Holy Thursday ceremony -- the first performed by a pontiff in prison and the first including women.
In another apparent break with tradition by Latin America's first pontiff, local prison ombudsman Angiolo Marroni said that one of the two girls taking part in the ceremony was Muslim.
The ceremony was held in the Casal del Marmo youth prison on the outskirts of Rome instead of a basilica in the city centre where popes usually celebrate the mass commemorating Jesus Christ's gesture of humility to his 12 disciples.
"I do this with all my heart because it is my duty as a priest, as a bishop. I have to be at your service. I love doing it because this is what the Lord has taught me," the 76-year-old pope said.
The ceremony was broadcast live on Vatican radio but other media were not allowed into the prison.
Catholic traditionalists are likely to be riled by the inclusion of women in the ceremony because of the belief that all of Jesus' disciples were male.
Christians believe that Jesus washed the feet of his apostles on the evening of their final meal together before his death, the Last Supper.
Local prison chaplain Gaetano Greco said he hoped the ritual would be "a positive sign in the lives" of the young offenders at the prison, which has around 50 inmates aged between 14 and 21.
Earlier on Thursday, the Argentinian pontiff told Catholic priests at a mass in St Peter's Basilica to stop their "soul-searching" and "introspection".
"We need to go out... to the outskirts where there is suffering, bloodshed, blindness that longs for sight and prisoners in thrall to many evil masters," he said.
He said the holy oil used to ordain priests was meant "for the edges" of society -- "for the poor, prisoners and the sick, for those who are in sorrow and alone".
Francis has called for the Church, which has been shaken by multiple scandals in recent years, to be more open and socially active as he begins his pontificate.
-- Unusual change of style --
His first fortnight as pontiff has been marked by an unusual change of style at the Vatican, but he has yet to tackle some of the big issues facing the Church including reform of the Vatican bureaucracy and bank.
The former archbishop of Buenos Aires, Jorge Mario Bergoglio, was known in Argentina for his strong social advocacy during his homeland's devastating economic crisis in recent years, his own humble lifestyle and his outreach in poor neighbourhoods.
Holy Thursday is the first of four days of intense spirituality culminating in Easter Sunday, the holiest day of the Christian calendar marking Jesus Christ's resurrection.
On Friday, Francis will recite the Passion of Christ -- the story of the last hours of Jesus' life -- in St Peter's Basilica, before presiding over the Via Crucis -- Way of the Cross -- ceremony by the Colosseum, where thousands of Christians were killed in Roman times.
While a frail Benedict, now 85, presided over last year's celebrations from under a canopy next to the Colosseum, Francis is expected to take part in the procession and even carry the wooden cross on his shoulder for part of the way.
On Saturday, the pontiff will take part in an evening Easter vigil in St Peter's Basilica. The Vatican has not yet said whether Francis will follow the tradition of baptising eight adult converts to the Catholic Church during the service.
On Sunday the Vatican's first non-European pope in nearly 1,300 years will celebrate Easter mass in front of tens of thousands of pilgrims in St Peter's Square and then pronounce the traditional "Urbi et Orbi" blessing to Rome and the world.
At his first general audience on Wednesday, Francis called on the world's 1.2 billion Catholics to reach out to "lost sheep" over the coming days.
"Holy Week challenges us to step outside ourselves so as to attend to the needs of others: those who long for a sympathetic ear, those in need of comfort or help," Francis said.