Abu Huraira reported God’s messenger as saying, “It is better that one of you should sit on live coals which burn his clothing and come in contact with his skin than that he should sit on a grave.”
‘Urwa b. az-Zubair said there were two men in Medina, one of whom made a niche when digging a grave, the other of whom did not. The people said that the one who came first should do as he was accustomed to do, and the one who made a niche came and made one for God’s messenger.
Jabir said God’s messenger forbade that graves should be plastered with gypsum, that any erection should be built over them, and that people should sit on them.