It is narrated on the authority of Abu Hurairah (RA) that the Messenger of Allah (ﷺ) (may peace and blessings be upon him) observed: Two (things) are found among men which are tantamount to unbelief: slandering one's lineage and lamentation on the dead.
Hadith Referenceصحيح مسلم / كتاب الإيمان / 67
Hadith Gradingمحدثین:أحاديث صحيح مسلم كلها صحيحة
Hadith Takhrij«أحاديث صحيح مسلم كلها صحيحة ، انفرد به مسلم - انظر ((تحفة الاشراف)) برقم (12458)»
Abu Hurairah (RA) reported: The Apostle of Allah (ﷺ) visited the grave of his mother and he wept, and moved others around him to tears, and said: I sought permission from my Lord to beg forgiveness for her but it was not granted to me, and I sought permission to visit her grave and it was granted to me. So visit the graves, for that makes you mindful of death.