It is narrated that Hazrat Anas (may Allah be pleased with him) used to act contrary to Umar bin Abdul Aziz (may Allah have mercy on him). Once, Umar bin Abdul Aziz (may Allah have mercy on him) asked him the reason for this, so he replied, "I saw the Prophet (peace and blessings be upon him) performing the prayer in a certain way. If you conform to that, I will pray with you, but if you act contrary to it, I will perform my prayer alone and go home."