What did the Prophet Muhammad (saw) say when 'Umar b. Khattab called (him) in a loud voice regarding prayer?
 'A'isha. the wife of the Apostle of Allah (may peace be upon him), reported:                      The Messenger of Allah (may peace be upon him) deferred one night the 'Isya' prayer. And this is called 'Atama. And the Messenger of Allah (may peace be upon him) did not come out till Umar b. Khattab told (him) that the women and children had gone to sleep. So the Messenger of Allah (may peace be upon him) came out towards them and said to the people of the mosque: None except you from the people of the earth waits for it (for the night prayer at this late hour), and it was before Islam had spread amongst people. And in the narration transmitted by Ibn Shihab the Messenger of Allah (may peace be upon him) is reported to have said: It is not meant that you should compel the Messenger of Allah (may peace be upon him) for prayer. And (this he said) when 'Umar b. Khattab called (the Holy Prophet) in a loud voice.