Pope Francis has said God loves everyone, “even the worst of us”, as he celebrated the birth of Christ in his Christmas Eve Mass in St Peter’s Basilica at the Vatican.

Francis said the birth of Jesus, which Christians commemorate on Christmas Day, was a reminder of God’s unconditional love for everyone, “even the worst of us”.

“God does not love you because you think and act the right way,” he said.

“You may have mistaken ideas, you may have made a complete mess of things, but the Lord continues to love you.”

At the same time though, he called for the faithful to allow themselves to be transformed by Jesus’ “crazy love” and to stop trying to change others.

“May we not wait for our neighbours to be good before we do good to them, for the church to be perfect before we love her, for others to respect us before we serve them.

“Let us begin with ourselves,” he said.

Pope Francis kisses the altar Credit: Alessandra Tarantino/AP

Francis has frequently emphasised his call for “personal conversion” in his reform-minded papacy, believing that true reform must come from within, rather than from on high.

He has similarly denounced the “holier-than-thou” attitude of doctrinal and legal purists, who have been critical of at his opening approach to gays, divorcees and people on the margins.

Those critics have seized on the sexual abuse and financial scandals that have hit his papacy.

The scandals are likely to follow Francis into 2020, with developments in a corruption investigation involving hundreds of millions of dollars in donations to the Holy See and the release of a report on what the Vatican knew about ex-cardinal Theodore McCarrick, who was defrocked for sexually abusing adults and minors,

Francis’ late-night mass kicks off a busy few days for the pope, including a Christmas Day speech, a New Year’s Eve vigil and a mass on New Year's Day.