ROME – In a traditional coda to the holiday season, Pope Francis on Sunday baptized 28 newborn children of Vatican employees, including thirteen girls and fifteen boys, during a Mass in the Sistine Chapel marking the feast of the Baptism of the Lord.

Sunday’s Mass in the Sistine Chapel is one of the rare intimate occasions during the holiday season, when a pontiff celebrates a liturgy not so much for the public or for the wider world, but for his immediate family within the Vatican itself, giving him an opportunity to act more as a parish priest than as a head of state or media celebrity.

In keeping with the informal feel of the event, Francis had no prepared text for his homily. He spoke extemporaneously, reflecting on the faith which parents pass onto their children as a source of “light” and linking that image to the baptismal candle which the parents received during the course of the ceremony.

As Francis was speaking, several of the babies began to cry, causing the pontiff to quip “the concert has begun!”

“I like to think that the first sermon Jesus gave in the stable was a cry,” he said, referring to the baby Jesus in the manger.

As he has in the past, Francis then invited the mothers present to breastfeed their children if they’re hungry, saying, “go ahead, don’t be afraid, like Mary breastfed Jesus.”

St. Pope John Paul II introduced the custom of baptizing the children of Vatican personnel on the feast of the Baptism of the Lord, which commemorates the Biblical scene in which Jesus is baptized by John the Baptist. The custom was continued under emeritus Pope Benedict XVI, and now under Francis.

“You’ve asked for the faith for your children, the faith that’s given in baptism,” the pope said. “That means a life of faith, because faith must be lived … to walk on the path of faith and give witness to the faith.

“Faith isn’t reciting the Creed on Sundays when we go to Mass, faith is believing in that which is the truth,” he said. “Faith is trusting in God, and you must teach them this with your example and your life.”

As a footnote, given the design of the Sistine Chapel, Sunday’s Mass marked one of the few times each year when Pope Francis celebrates using the ad orientem posture associated with the Latin Mass used before the Second Vatican Council, meaning facing East and thus with his back to the congregation.

Also on Sunday, the pope’s charity office announced that it would keep the shelters it operates in the vicinity of the Vatican open day and night in order to give homeless persons in the area refuge from an unusually cold spell in Rome, which has seen nighttime temperatures over the last few days fall below freezing.

The charity office also announced that it would be positioning cars it owns around the area surrounding the Vatican, so that homeless persons who don’t wish to move from their usual locations can sleep in them during the nights in order to fight off the cold.

Two of those cars have been placed on the Via della Conciliazione, the broad street that leads up to St. Peter’s Square, and the Italian newspaper La Repubblica reported on Sunday that one of them had been occupied the previous evening by an 85-year-old homeless woman.

Sunday’s baptisms will not be the last for Pope Francis in the month of January.

On January 14, in the chapel of the Casa Santa Marta, the residence on Vatican grounds where the pope lives, he’s also scheduled to baptize eight children of families from Amatrice and Accumoli, towns in central Italy devastated by an Aug. 24 earthquake that left nearly 300 people dead.

Pope Francis visited the two sites in early October, pledging his prayers for the victims and his solidarity with the survivors.

The local bishop, Domenico Pompili, explained that when Francis came to Amatrice, a mother presented her child to the pope and asked about the possibility of Francis performing the baptism. From there, the idea was born of having the pope baptize children of survivors in a special Vatican ceremony.