Is prayer permissible upon a grave?

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Prayer is permissible upon a grave. This ruling is affirmed by Ahmad, who stated that there is no issue with it. This practice was performed by several Companions of the Messenger of Allah (peace be upon him). The evidence for this is the hadith of Ibn Abbas, where the Prophet (peace be upon him) approached a fresh grave, the people formed rows behind him, and he performed the prayer, saying the Takbir four times. This narration is Muttafaq 'alayh (agreed upon by Bukhari and Muslim).