The Prophet ﷺ said, "The purification of every hide is its tanning."
عن النبي ﷺ قال: طهور كل أديم دباغه.
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Daraqutni (124) and Bayhaqi (21/1) both narrated it through the route of Ibrahim bin Haytham, who said, Ali bin Ayyash told us, Muhammad bin Mutarrif told us, Zayd bin Aslam told us, from Ata bin Yasar, from Ayesha, and he mentioned it.Its chain is hasan due to the discussion surrounding Ibrahim bin Haytham, though his hadith is hasan. Daraqutni graded it hasan, and Bayhaqi said, "Its narrators are trustworthy." Dhahabi said in al-Mizan, "Daraqutni and Khatib deemed him trustworthy, and Ibn Adi mentioned him in al-Kamil, saying, His hadith is sound except for the hadith of the mouse, for which the people accused him of lying and confronted him about it, the first of them being Bardiji. His hadiths are good. I have examined much of his hadith and found no objectionable hadith attributable to him."