The Messenger of Allah ﷺ said, "When one of you cleans himself with stones, let him use an odd number."
وقال رسول الله إذا استجمر أحدكم فليوتر
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This hadith is also sahih, and it is in the individual Sahifah under number 52. The two Shaykhs (Bukhari and Muslim) did not narrate it through the route of the Sahifah, nor with this wording, from the hadith of Abu Hurairah. It has already appeared as number 7445 with this wording, through the narration of Araj, worded as, "When one of you cleanses himself with stones, let him do so in odd numbers." As for its meaning, it has already appeared repeatedly, among hadiths whose sourcing we detailed in their places, including numbers 7220, 7340, and 8063.