Sayyiduna Anas bin Malik (may Allah be pleased with him) used to stay behind (i.e., not pray with) Umar bin Abdul Aziz (may Allah have mercy on him) in prayer. (One day) Umar bin Abdul Aziz asked him: What makes you do this? He replied: I saw the Messenger of Allah (peace and blessings be upon him) praying; when you conform to that prayer, I pray with you, but when you differ from it, I perform the prayer (on time) and go home.