ROME—Pope Francis ended 2019 in embarrassment when he angrily slapped the hand of a woman who had pulled on his own while he was greeting pilgrims on New Year’s Eve. He began 2020 with a public apology for losing his patience and setting a “bad example.”

It was a fitting coda to a year in which the pope addressed one scandal—the Catholic Church’s sex-abuse crisis—only to become embroiled in another, over the Vatican’s murky finances.

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