Jundub Ibn Abd-Allah al-Bajali said that he heard RasulAllah (saw) say, five days before he died: "Verily those before you took the graves of their Prophets and righteous people as places of worship, so do not take the graves as places of worship. Indeed I forbid you from this!" (Muslim; Abu Awaanah, 1/104; and others
It was narrated from Abu Hurayrah (ra) that RasulAllah (saw) said: "O Allah, do not turn my grave into an idol. May the curse of Allah be upon those who take the graves of their Prophets as places of worship." (Ahmad; Ibn Sa‘d, 2/241-242; and others)
Abd-Allah Ibn Sharjil Hasanah said: "I saw Uthman Ibn Affan (ra) order the leveling of the graves. So it was said to him: This is the grave of Umm Amr the daughter of Uthman! However, he commanded that it too should be leveled." (Ibn Abi Shaybah, al-Musannaf, 4/138; Abu Zur‘ah, at-Tarikh, 22/2)
It was narrated from Abu'l-Hayyaaj al-Asadi who said: "Ali Ibn Abi Talib (ra) said to me: Shall I not send you for what RasulAllah (saw) sent me? That you deface all statues and pictures and that you level all elevated graves." (Muslim; Abu Dawud; Nasai; and others)
Abu Burdah said: "Abu Musa al-Ash‘ari (ra) advised us before he died, saying: You should hasten with my janaazah…and do not put in my lahad (a cleavage in the side of the grave where the body is placed) anything that will come between me and the earth, nor build anything over my grave. So bear witness that I am free of those women who shave their heads, tear their clothes or beat their cheeks. They said: Did you hear anything about this? He said: Yes, from RasulAllah (saw)!" (Ahmad)
Imam Qurtubi points out that how Allah (swt) protected the grave of RasulAllah (saw) in return for an answer to his prayer, which he (saw) said: “O Allah! Do not let my grave become an idol that people worship.” (al-Muwatta; Ahmad; Ibn Sa‘d and others), from becoming a direction of prayer: "Therefore,...