Abdullah bin Abbas narrates that when Abu Bakr arrived Umar was addressing the people. He said, “O‘ Umar sit down.” Umar did not sit but people left him and turned thier attention towards Abu Bakr, who then said, “Those amongst you who worshipped Muhammadsaw should know that Muhammadsaw has died. Those who worshipped Allah should be satisfied that Allah is alive and is impervious to suffering death. Allah has said that Muhammadsaw is but a messenger. Verily all Messengers have passed away before him. If then he dies or is slain, will you turn back on your heels? Those among you who turn back on their heels will not harm Allah a whit and Allah will reward those who are thankful.” (Bukhari Kitab-ul-Mughazi Chapter Prophet's illness and death)
In another narration it said that Umarra was in such an agitated state that with his sword drawn he promised to kill anyone who said that the Holy Prophetsaw had died. Abu Bakrra on learning of these disturbing developments removed the covering from Holy Prophet'ssaw face, kissed his forehead, and said that surely Allah would not subject him to two deaths. He understood that Holy Prophetsaw was not going to return. He then gathered everyone in the Masjid-al-Nabwi and recited 3:145:
And Muhammad is but a messenger. Verily all Messengers have passed away before him. If then he dies or is slain, will you turn back on your heels? (3:145)
Those who were in doubt were at once convinced. Umar collapsed to the ground. It is said that it felt like this verse was being revealed for the first time. With great wisdom Abu Bakr had brought the delicate situation under control. This verse was sufficient to prove to all present that Muhammadsaw had passed away like the earlier prophets. If it was the general belief that even one among the earlier prophets was still alive surely Abu Bakr's reasoning would have failed. If khalat did not mean death, Umar could not have been convinced and would have protested and brought up the case of Jesus. On the contrary no one uttered a word of protest and all concluded on the authority of this verse that Muhammadsaw had died like prophets before him.
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