The Prophet ﷺ passed by two graves and said, "These two are being punished, and they are not being punished for something major. One of them did not shield himself from urine, and the other used to walk about spreading slander."Then he took a fresh palm branch, split it in two, and planted one piece on each grave.They asked, "Messenger of Allah, why did you do this?"He replied, "Perhaps their punishment will be lessened as long as these have not dried out."Muhammad bin Muthanna said, Waki narrated to us, saying Amash narrated to us, saying I heard Mujahid say the like of it, "He did not shield himself from his urine."
حدثنا محمد بن المثنى قال حدثنا محمد بن خازم قال حدثنا الأعمش عن مجاهد عن طاوس
مر النبي ﷺ بقبرين فقال إنهما ليعذبان وما يعذبان في كبير أما أحدهما فكان لا يستتر من البول وأما الآخر فكان يمشي بالنميمة ثم أخذ جريدة رطبة فشقها نصفين فغرز في كل قبر واحدة قالوا يا رسول الله لم فعلت هذا قال لعله يخفف عنهما ما لم ييبسا وقال محمد بن المثنى وحدثنا وكيع قال حدثنا الأعمش قال سمعت مجاهدا مثله يستتر من بوله
Both of them (Bukhari and Muslim) related together the hadith of Amash, from Mujahid, from Tawus, from Ibn Abbas (concerning the story of the two graves, and that one of the two [occupants] used to fail to cleanse himself properly after urinating). Mansur differed with him and dropped Tawus from the chain. Bukhari alone related the hadith of Mansur alone, with Tawus dropped from it.
Hafiz, may Allah have mercy on him, said in the introduction (p. 350, printing S), after mentioning Daraqutni's statement, "Bukhari narrated this hadith in the Book of Purification from Uthman bin Abu Shayba from Jareer, and in the Book of Manners from Muhammad bin Salam from Ubayda, both of them from Mansur, with this wording. He also narrated it through another route from the hadith of Amash, and the remaining five imams narrated it from the hadith of Amash as well."Hafiz, may Allah have mercy on him, then said, "In reality this is not a defect, because Mujahid was not described as one who practiced tadlis, and his hearing from Ibn Abbas is sahih in a number of hadiths. Mansur, in their view, is more precise than Amash, though Amash is also among the memorizers of hadith. So however the hadith is traced, it traces back to a trustworthy narrator, and however the chain is traced, it remains connected. Something like this does not undermine the soundness of the hadith, so long as its narrator does not practice tadlis. The two Shaykhs (Bukhari and Muslim) frequently narrated things of this sort, and Daraqutni did not exhaustively cover his criticism. And Allah grants success." End of quote.Hafiz also said in Fath al-Bari, volume 1, page 317, printing S, "His narrating it in both forms indicates that he considered both of them sahih in his view. This is to be understood as meaning that Mujahid heard it from Tawus from Ibn Abbas, and then heard it from Ibn Abbas directly without an intermediary, or the reverse. This is supported by the fact that his wording from Tawus contains an addition beyond what is in his narration from Ibn Abbas. Ibn Hibban explicitly stated that both routes are sahih together." End of quote.