Kharija ibn Zayd ibn Thabit خارجة بن زيد بن ثابت الأنصاري · The Book of Funerals

"When any one of you sees a funeral and is not walking with it, let him stand up until it has passed him, or until (the body) is placed (in the grave) before if passes him."

"Dig graves and dig them well, and bury two or three (together), and put in first the one who knew the Qur'an most."