Hazrat Musa عليه السلام praying in the Grave
أَخْبَرَنَا عَلِيُّ بْنُ خَشْرَمٍ، قَالَ حَدَّثَنَا عِيسَى، عَنْ سُلَيْمَانَ التَّيْمِيِّ، عَنْ أَنَسِ بْنِ مَالِكٍ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " مَرَرْتُ لَيْلَةَ أُسْرِيَ بِي عَلَى مُوسَى عَلَيْهِ السَّلاَمُ وَهُوَ يُصَلِّي فِي قَبْرِهِ " .
It was narrated that Sayyiduna Anas bin Malik رضی اللہ تعالٰی عنہ said: "The Messenger of Allah (ﷺ) said: 'On the night on which I was taken on the Night Journey, I passed by Musa, peace be upon him, and he was praying in his grave.'"
Sunan an-Nasa'i 1634
Chapter 15: Mentioning the prayer of Prophet Musa and the different reports from Sulaiman At-Taimi about it, Book 20: The Book of Qiyam Al-Lail (The Night Prayer) and Voluntary Prayers During the Day