Ibn Shihab reported,

A man confessed to committing adultery during the time of the Messenger of Allah ﷺ and testified against himself four times, so the Messenger of Allah ﷺ gave the order concerning him and he was stoned.Ibn Shihab said, "It is for this reason that a man is held accountable on the basis of his own confession."

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عن ابن شهاب أنه أخبره

أن رجلا اعترف على نفسه بالزنا على عهد رسول الله ﷺ وشهد على نفسه أربع مرات فأمر به رسول الله ﷺ فرجم قال ابن شهاب فمن أجل ذلك يؤخذ الرجل باعترافه على نفسه