The very first way the Child Jesus revealed the love and goodness of the Father was in smiling at his parents, just "like every newborn baby in this world," Pope Francis said Saturday.

"When we look at a newborn baby, we are led to smile at it, and if a smile blossoms on its small face, then we experience a simple, unsophisticated emotion," the pope said Dec. 21.

"The child responds to our gaze, but his smile is much more 'powerful' because it is new, pure, like spring water," he continued.

Pope Francis spoke about smiling during his Christmas greeting to employees of Vatican City State and their families in the Pope Paul VI hall.

The same exchange which happens between parents and their smiling infants happened in a unique way between the Child Jesus and Joseph and Mary, he said.

"The Virgin and her husband, with their love, made the smile blossom on the lips of their newborn baby. But when that happened, their hearts were filled with a new joy from Heaven. And the small stable in Bethlehem lit up."

"Jesus is the smile of God," the pope said. "And they, the Virgin Mary and St. Joseph, for their great faith have been able to accept that message, have recognized in Jesus' smile the mercy of God for them and for all those who waited for his coming, the coming of the Messiah, the Son of God, the King of Israel."

During Christmas, he encouraged people to look at the Nativity scene and to reflect on this smile of the Christ Child, "feeling that there God smiles at us, and smiles at all the poor of the earth, at all those who await salvation, who hope for a more fraternal world, where there are no more wars and violence, where every man and woman can live in his dignity as son and daughter of God."

He noted that "sometimes it becomes difficult to smile, for many reasons," and that this is the time when people need Jesus. "Only He can help us," he said.

Those working inside the Vatican and in the offices of the Holy See, he added, always need to be renewed by the smile of the Baby Jesus, "allowing his unarmed goodness to purify us of the scum that often encrusts our hearts, and prevents us from giving our best."

He acknowledged that "work is work" and not always the place of the fullest and richest self-expression but noted that it is also the place at which people spend a good part of their day.

"We are convinced that the quality of work is accompanied by the human quality of relationships and manner of life," he said, adding that "this is especially true for us, who work in the service of the Church and in the name of Christ."