Abu Hurairah (May Allah be pleased with him) reported: The Messenger of Allah (peace be upon him) said, “Do not make my grave a place of festivity, and supplicate Allah for me, for your supplication reaches me wherever you are.”
(Abu Dawud)

“The world is the believer’s prison and the infidel’s Jannah”. (Muslim)

Abdullah bin ‘Amr bin Al-As (May Allah be pleased with them) reported: I heard the Messenger of Allah (peace be upon him) saying: “Whoever supplicates Allah to exalt my mention, Allah will exalt his mention ten times.” [Muslim]

Abu Umamah Al-Bahili RA reported: Messenger of Allah (peace be upon him) said, “I guarantee a house in Jannah for one who gives up arguing, even if he is in the right; and I guarantee a home in the middle of Jannah for one who abandons lying even for the sake of fun; and I guarantee...

Jabir RA said: The Messenger of Allah (peace be upon him) forbade that the graves should be plastered (made into permanent structures), used as sitting places (for the people) or building over them.
(Muslim)