Pope Francis celebrated his first Christmas Eve mass at St. Peter's Basilica at the Vatican on Tuesday. The widely liked Argentinean pontiff took the opportunity to preach his message of humility and charity by emphasizing Jesus Christ’s humble beginnings.

"You are immense, and you made yourself small; you are rich, and you made yourself poor; you are all-powerful and you made yourself vulnerable,” he said during mass, according to the Associated Press.

In the past nine months, the pope has dedicated most of his time to the vulnerable members of society-- to children and to those who are poor. He added that when Jesus was born, many of the first people to find out about the news were shepherds. At the time, shepherds were though to be “outcasts” and “among the last.”

During the mass, Pope Francis, 77, carried a figurine of a newly born Jesus and then kissed its knee. Normally, an aide would carry the statue for the pope during Christmas Eve mass.

The AP added the pope then began to talk about light and darkness. He called Jesus "the light who brightens the darkness” and even added his personal history to his mass.

"There are both bright and dark moments, lights and shadows." He added: "If our heart is closed, if we are dominated by pride, deceit, self-seeking, then darkness falls within us and around us."

He said his message also applies to the Vatican, adding there is no place for religious hierarchy. Instead, he said, the Catholic Church should serve people who are in need.

On Wednesday, for Christmas Day, Pope Francis is set to give his Christmas message, which is supposed to be for the world, as he stands from the basilica's central balcony and overlooks St. Peter's Square.

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