What did Abu Bakr (may Allah be pleased with him) when he entered the Mosque and saw the Prophet Muhammad (saw)?
 Narrated `Aisha:                     Abu Bakr came from his house at As-Sunh on a horse. He dismounted and entered the Mosque, but did not speak to the people till he entered upon `Aisha and went straight to Allah's Apostle who was covered with Hibra cloth (i.e. a kind of Yemenite cloth). He then uncovered the Prophet's face and bowed over him and kissed him and wept, saying, "Let my father and mother be sacrificed for you. By Allah, Allah will never cause you to die twice. As for the death which was written for you, has come upon you." Narrated Ibn `Abbas: Abu Bakr went out while `Umar bin Al-Khattab was talking to the people. Abu Bakr said, "Sit down, O `Umar!" But `Umar refused to sit down. So the people came to Abu Bakr and left `Umar. Abu Bakr said, "To proceed, if anyone amongst you used to worship Muhammad , then Muhammad is dead, but if (anyone of) you used to worship Allah, then Allah is Alive and shall never die. Allah said:--"Muhammad is no more than an Apostle, and indeed (many) apostles have passed away before him..(till the end of the Verse )......Allah will reward to those who are thankful." (3.144) By Allah, it was as if the people never knew that Allah had revealed this Verse before till Abu Bakr recited it and all the people received it from him, and I heard everybody reciting it (then). Narrated Az-Zuhri: Sa`id bin Al-Musaiyab told me that `Umar said, "By Allah, when I heard Abu Bakr reciting it, my legs could not support me and I fell down at the very moment of hearing him reciting it, declaring that the Prophet had died."