Musnad Abu Ya'la al-Mawsili 7:25

Abu Bakr ibn Abi Shaybah narrated to us, Zayd ibn al-Hubab narrated to us, Musa ibn Ubaydah narrated to us, Qays ibn Abd al-Rahman ibn Abi Sa'sa'ah narrated to me, from Sa'd ibn Ibrahim, from his father, from his grandfather Abd al-Rahman, who said: There would not depart from the Messenger of Allah (may Allah bless him and grant him peace) five or four of the companions of the Prophet (may Allah bless him and grant him peace) regarding what would befall him of his needs by night and by day. He said: So I came to him and he had gone out, so I followed him. He entered one of the gardens of al-Aswaf and prayed, then he prostrated and prolonged the prostration. I said: "Allah has taken his soul." He said: Then he raised his head and called me, saying: "What is the matter with you?" I said: "O Messenger of Allah, you prolonged the prostration, so I said: 'Allah has taken the soul of the Messenger of Allah, I will never see him again.'" He said: "I prostrated in gratitude to my Lord for what He has tested me with regarding my nation. Whoever from my nation sends a prayer upon me once, ten good deeds are written for him, and ten evil deeds are erased from him."