Just to add to the other answers here, there’s the story of Angulimala, a serial killer, which is often given as encouragement to those who have done awful things in their life, for instance murderers in prison as part of Buddhist prison chaplaincy. According to the story, he killed 999 people for their little fingers out of devotion to his own teacher who had asked him to do this. He was just about to kill his thousandth who would have been his own mother on her way to plead with him when Buddha encountered him, and the story is about how Buddha got him to change his ways.
Later, according to the story in the Pali Canon, he encounters a woman in a difficult labor and Buddha gave him a prayer to say to her, as a result of which she safely gives birth to her child. He eventually realized enlightenment as an arhat in that very life.
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