When the Prophet ﷺ passed away, there were two men in Medina, one who dug graves with a side niche and another who dug them as a straight trench. The people said, "Let us seek guidance from our Lord and send for both of them. Whichever one arrives first, we will leave the matter to him." So they sent for them, and the one who dug graves with a side niche arrived first, so they prepared a grave with a side niche for the Prophet ﷺ.
لما توفي النبي ﷺ كان بالمدينة رجل يلحد، وآخر يضرح، فقالوا: نستخير ربنا ونبعث إليهما، فأيهما سبق تركناه، فأرسل إليهما، فسبق صاحب اللحد، فلحدوا للنبي ﷺ.
Ibn Majah (1557) narrated it, he said, Mahmud bin Ghaylan told us, he said, Hashim bin Qasim told us, he said, Mubarak bin Fadala told us, he said, Humayd Tawil told me, from Anas, and he mentioned the hadith. Hashim bin Qasim is Abu Nadr, the teacher of Ahmad, and Ahmad narrated it from him in his Musnad (12415) in similar fashion. Its isnad is hasan on account of Mubarak bin Fadala, for he is "truthful but practices tadlis and smooths over defects." Abu Zura said, "He practices tadlis frequently, but when he says, 'He told us,' then he is reliable." Here he has explicitly stated the mode of narration, and Hafiz graded it hasan in Talkhis (2/128). Busiri said, "Its isnad is sahih and its narrators are reliable," but the correct view is as I have stated.In some of the narrations it is mentioned that the one who dug the trench grave was Abu Ubayda, and the one who dug the niche grave was Abu Talha. The word "yalhad" refers to the work of making the side opening in the grave for the place of the deceased, because it slants away from the middle of the grave toward its side. And "yadrah" refers to the work of making the darih, which is the grave itself, from the word darh, meaning a slit in the ground.Abu Ubayda is Ibn Jarrah, that is, Amir bin Abdullah bin Jarrah, the Qurashi, the Makkan, for whom the Prophet ﷺ testified to Paradise, and whom he named the Trustee of the Nation. He has many notable merits, and he died in 18 AH during the plague of Amwas.Abu Talha is Zayd bin Sahl, the Khazraji, the Najjari, the Ansari, from the maternal relatives of the Prophet ﷺ. He was one of the notable participants of Badr, and one of the twelve leaders on the night of Aqabah, and he has many notable merits. He died in 34 AH.