Sunan Abi Dawud 3173
سنن أبي داود#3173SahihNarrated Abu Sa’id Al Khudri :The Messenger of Allah (ﷺ) as saying: When you follow a funeral, do not sit until the bier is placed (on the ground). Abu Dawud said: This tradition has been narrated by al-Thawri (i.e. Sufyan) from Suhail, from his father on the authority of Abu Hurairah. This version has: until it (the bier) is placed on the ground. It has also been narrated by Abu Mu'wiyah from Suhail. This has: Until it is placed in the grave. Abu Dawud said: Sufyan's version is more guarded than that of Abu Mu'awiyah
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Al-AlbaniSahih
Muhammad Muhyi Al-Din Abdul HamidSahih
Zubair Ali ZaiIsnaad Sahih
In-book reference: 21:85