Remarking on the “so much consumerism that has packaged the mystery” of Christmas, Francis said there was a danger the day’s meaning could be forgotten.

But, he said, Christmas focuses attention on “the problem of our humanity – the indifference produced by the greedy rush to possess and consume”.

“Jesus was born poor, lived poor and died poor,” Francis said. “He did not so much talk about poverty as live it, to the very end, for our sake.”

Francis urged people to “not let this Christmas pass without doing something good”.

When the Mass ended, the pope, pushed in a wheelchair by an aide, moved down the basilica with a life-sized statue of Baby Jesus on his lap and flanked by several children carrying bouquets. The statue then was placed in a manger in a crèche scene in the basilica.

Francis, 86, has been using a wheelchair to navigate long distances due to a painful knee ligament, and a cane for shorter distances.

Traditionally, Catholics mark Christmas Eve by attending Mass at midnight. But over the years, the starting time at the Vatican has crept earlier, reflecting the health or stamina of popes and then the pandemic.

Two years ago, the start of Christmas Eve Mass in St Peter’s Basilica was moved up to 7.30pm to allow faithful to get home before for a nighttime curfew imposed by the Italian government as a measure to combat the COVID-19 pandemic. Although virtually all pandemic-triggered restrictions have long been lifted in Italy, the Vatican kept to the early start time.

During Saturday evening’s service, a choir sang hymns. Clusters of potted red poinsettia plants near the altar contrasted with the cream-coloured vestments of the pontiff.

On Sunday, tens of thousands of Romans, tourists and pilgrims were expected to crowd into St Peter’s Square to hear Pope Francis deliver an address on world issues and give his blessing. The speech, known in Latin as “Urbi et Orbi” (to the city and to the world), generally is an occasion to review crises including war, persecution and hunger, in many parts of the globe.