Narrated Al-Bara:

The Prophet (ﷺ) prayed facing Bait-ulMaqdis (i.e. Jerusalem) for sixteen or seventeen months but he wished that his Qibla would be the Ka`ba (at Mecca). (So Allah Revealed (2.144) and he offered `Asr prayers(in his Mosque facing Ka`ba at Mecca) and some people prayed with him. A man from among those who had prayed with him, went out and passed by some people offering prayer in another mosque, and they were in the state of bowing. He said, "I, (swearing by Allah,) testify that I have prayed with the Prophet (ﷺ) facing Mecca." Hearing that, they turned their faces to the Ka`ba while they were still bowing. Some men had died before the Qibla was changed towards the Ka`ba. They had been killed and we did not know what to say about them (i.e. whether their prayers towards Jerusalem were accepted or not). So Allah revealed:-- "And Allah would never make your faith (i.e. prayer) to be lost (i.e. your prayers offered (towards Jerusalem). Truly Allah is Full of Pity, Most Merciful towards mankind." (2.143)

Narrated Abu Sa`id:

Allah's Messenger (ﷺ) said, "Noah and his nation will come (on the Day of Resurrection and Allah will ask (Noah), "Did you convey (the Message)?' He will reply, 'Yes, O my Lord!' Then Allah will ask Noah's nation, 'Did Noah convey My Message to you?' They will reply, 'No, no prophet came to us.' Then Allah will ask Noah, 'Who will stand a witness for you?' He will reply, 'Muhammad and his followers (will stand witness for me).' So, I and my followers will stand as witnesses for him (that he conveyed Allah's Message)." That is, (the interpretation) of the Statement of Allah: "Thus we have made you a just and the best nation that you might be witnesses Over mankind .." (2.143)

Narrated Abu Sa`id Al-Khudri:

Allah's Messenger (ﷺ) said, "Noah will be called on the Day of Resurrection and he will say, 'Labbaik and Sa`daik, O my Lord!' Allah will say, 'Did you convey the Message?' Noah will say, 'Yes.' His nation will then be asked, 'Did he convey the Message to you?' They will say, 'No Warner came to us.' Then Allah will say (to Noah), 'Who will bear witness in your favor?' He will say, 'Muhammad and his followers. So they (i.e. Muslims) will testify that he conveyed the Message. And the Apostle (Muhammad) will be a witness over yourselves, and that is what is meant by the Statement of Allah "Thus We have made of you a just and the best nation that you may be witnesses over mankind and the Apostle (Muhammad) will be a witness over yourselves." (2.143)

Narrated Al-Bara' (bin 'Azib):

When the Prophet (ﷺ) came to Medina, he stayed first with his grandfathers or maternal uncles from Ansar. He offered his prayers facing Baitul-Maqdis (Jerusalem) for sixteen or seventeen months, but he wished that he could pray facing the Ka'ba (at Mecca). The first prayer which he offered facing the Ka'ba was the 'Asr prayer in the company of some people. Then one of those who had offered that prayer with him came out and passed by some people in a mosque who were bowing during their prayers (facing Jerusalem). He said addressing them, "By Allah, I testify that I have prayed with Allah's Messenger (ﷺ) facing Mecca (Ka'ba).' Hearing that, those people changed their direction towards the Ka'ba immediately. Jews and the people of the scriptures used to be pleased to see the Prophet (ﷺ) facing Jerusalem in prayers but when he changed his direction towards the Ka'ba, during the prayers, they disapproved of it.

Al-Bara' added, "Before we changed our direction towards the Ka'ba (Mecca) in prayers, some Muslims had died or had been killed and we did not know what to say about them (regarding their prayers.) Allah then revealed: And Allah would never make your faith (prayers) to be lost (i.e. the prayers of those Muslims were valid).' " (2:143).