Allah said:

﴿ظˆظژظƒظژط°ظژظ„ظگظƒظژ ط¬ظژط¹ظژظ„ظ’ظ†ظژظ€ظƒظڈظ…ظ’ ط£ظڈظ…ظ‘ظژط©ظ‹ ظˆظژط³ظژط·ظ‹ط§ ظ„ظ‘ظگطھظژظƒظڈظˆظ†ظڈظˆط§ظ’ ط´ظڈظ‡ظژط¯ظژط¢ط،ظژ ط¹ظژظ„ظژظ‰ ط§ظ„ظ†ظ‘ظژط§ط³ظگ ظˆظژظٹظژظƒظڈظˆظ†ظژ ط§ظ„ط±ظ‘ظژط³ظڈظˆظ„ظڈ ط¹ظژظ„ظژظٹظ’ظƒظڈظ…ظ’ ط´ظژظ‡ظگظٹط¯ظ‹ط§﴾

(Thus We have made you ﴿true Muslims﴾, a Wasat (just) (and the best) nation, that you be witnesses over mankind and the Messenger (Muhammad ) be a witness over you.)

Allah stated that He has changed our Qiblah to the Qiblah of Ibrahim and chose it for us so that He makes us the best nation ever. Hence, we will be the witnesses over the nations on the Day of Resurrection, for all of them will then agree concerning our virtue. The word Wasat in the Ayah means the best and the most honored. Therefore, saying that (the Prophet's tribe) Quraysh is in the Wasat regarding Arab tribes and their areas, means the best. Similarly, saying that Allah's Messenger was in the Wasat of his people, means he was from the best subtribe. Also, `Asr, the prayer that is described as `Wusta' (a variation of the word Wasat), means the best prayer, as the authentic collections of Ahadith reported. Since Allah made this Ummah (Muslim nation) the Wasat, He has endowed her with the most complete legislation, the best Manhaj (way, method, etc.,) and the clearest Madhhab (methodology, mannerism, etc). Allah said:

﴿ظ‡ظڈظˆظژ ط§ط¬ظ’طھظژط¨ظژظ€ظƒظڈظ…ظ’ ظˆظژظ…ظژط§ ط¬ظژط¹ظژظ„ظژ ط¹ظژظ„ظژظٹظ’ظƒظ…ظ’ ظپظگظ‰ ط§ظ„ط¯ظ‘ظگظٹظ†ظگ ظ…ظگظ†ظ’ ط­ظژط±ظژط¬ظچ ظ…ظ‘ظگظ„ظ‘ظژط©ظژ ط£ظژط¨ظگظٹظƒظڈظ…ظ’ ط¥ظگط¨ظ’ط±ظژظ‡ظگظٹظ…ظژ ظ‡ظڈظˆظژ ط³ظژظ…ظ‘ظژظ€ظƒظڈظ…ظڈ ط§ظ„ظ’ظ…ظڈط³ظ’ظ„ظگظ…ظگظٹظ†ظژ ظ…ظگظ† ظ‚ظژط¨ظ’ظ„ظڈ ظˆظژظپظگظ‰ ظ‡ظژظ€ط°ظژط§ ظ„ظگظٹظژظƒظڈظˆظ†ظژ ط§ظ„ط±ظ‘ظژط³ظڈظˆظ„ظڈ ط´ظژظ‡ظگظٹط¯ط§ظ‹ ط¹ظژظ„ظژظٹظ’ظƒظڈظ…ظ’ ظˆظژطھظژظƒظڈظˆظ†ظڈظˆط§ظ’ ط´ظڈظ‡ظژط¯ظژط¢ط،ظژ ط¹ظژظ„ظژظ‰ ط§ظ„ظ†ظ‘ظژط§ط³ظگ﴾

(He has chosen you (to convey His Message of Islamic Monotheism to mankind), and has not laid upon you in religion any hardship: it is the religion of your father Ibrahim. It is He (Allah) Who has named you Muslims both before and in this (the Qur'an), that the Messenger (Muhammad ) may be a witness over you and you be witnesses over mankind!) (22:78)

Moreover, Imam Ahmad reported that Abu Sa`id narrated: Allah's Messenger said:

آ«ظٹظڈط¯ظ’ط¹ظژظ‰ ظ†ظڈظˆط­ظŒ ظٹظژظˆظ’ظ…ظژ ط§ظ„ظ’ظ‚ظگظٹظژط§ظ…ط©طŒ ظپظژظٹظڈظ‚ظژط§ظ„ظڈ ظ„ظژظ‡ظڈ: ظ‡ظژظ„ظ’ ط¨ظژظ„ظ‘ظژط؛ظ’طھظژطں ظپظژظٹظژظ‚ظڈظˆظ„ظڈ: ظ†ظژط¹ظژظ…ظ’طŒ ظپظژظٹظڈط¯ظ’ط¹ظژظ‰ ظ‚ظژظˆظ’ظ…ظڈظ‡ظڈ ظپظژظٹظڈظ‚ظژط§ظ„ظڈ ظ„ظژظ‡ظڈظ…ظ’: ظ‡ظژظ„ظ’ ط¨ظژظ„ظ‘ظژط؛ظژظƒظڈظ…ظ’ ظپظژظٹظژظ‚ظڈظˆظ„ظڈظˆظ†ظژ: ظ…ظژط§ ط£طھظژط§ظ†ظژط§ ظ…ظگظ†ظ’ ظ†ظژط°ظگظٹط±ظچ ظˆظژظ…ظژط§ ط£طھظژط§ظ†ظژط§ ظ…ظگظ†ظ’ ط£ظژط­ظژط¯ظچطŒ ظپظژظٹظڈظ‚ظژط§ظ„ظڈ ظ„ظگظ†ظڈظˆط­: ظ…ظژظ†ظ’ ظٹظژط´ظ’ظ‡ظژط¯ظڈ ظ„ظژظƒظژطں ظپظژظٹظژظ‚ظڈظˆظ„ظڈ: ظ…ظڈط­ظژظ…ظ‘ظژط¯ظŒ ظˆظژط£ظڈظ…ظ‘ظژطھظڈظ‡ظڈطŒ ظ‚ط§ظ„ ظپظژط°ظ„ظگظƒظژ ظ‚ظژظˆظ’ظ„ظڈظ‡ظڈ:

﴿ظˆظژظƒظژط°ظژظ„ظگظƒظژ ط¬ظژط¹ظژظ„ظ’ظ†ظژظ€ظƒظڈظ…ظ’ ط£ظڈظ…ظ‘ظژط©ظ‹ ظˆظژط³ظژط·ظ‹ط§﴾

ظ‚ظژط§ظ„ظژ: ظˆط§ظ„ظ’ظˆظژط³ظژط·ظڈ ط§ظ„ظ’ط¹ظژط¯ظ’ظ„ظڈطŒ ظپظژطھظڈط¯ظ’ط¹ظژظˆظ† ظپظژطھظژط´ظ’ظ‡ظژط¯ظڈظˆظ†ظژ ظ„ظژظ‡ظڈ ط¨ظگط§ظ„ظ’ط¨ظژظ„ظژط§ط؛ظگ ط«ظڈظ…ظ‘ظژ ط£ظژط´ظ’ظ‡ظژط¯ظڈ ط¹ظژظ„ظژظٹظ’ظƒظڈظ…آ»

(Nuh will be called on the Day of Resurrection and will be asked, `Have you conveyed (the Message)' He will say, `Yes.' His people will be summoned and asked, `Has Nuh conveyed (the Message) to you' They will say, `No warner came to us and no one (Prophet) was sent to us.' Nuh will be asked, `Who testifies for you' He will say, `Muhammad and his Ummah.')

This is why Allah said:

﴿ظˆظژظƒظژط°ظژظ„ظگظƒظژ ط¬ظژط¹ظژظ„ظ’ظ†ظژظ€ظƒظڈظ…ظ’ ط£ظڈظ…ظ‘ظژط©ظ‹ ظˆظژط³ظژط·ظ‹ط§﴾

(Thus We have made you a Wasat nation.)

The Prophet said; (The Wasat means the `Adl (just). You will be summoned to testify that Nuh has conveyed (his Message), and I will attest to your testimony.)

It was also recorded by Al-Bukhari, At-Tirmidhi, An-Nasa'i and Ibn Majah.

Imam Ahmad also reported that Abu Sa`id Khudri narrated: Allah's Messenger said:

آ«ظٹظژط¬ظگظٹط،ظڈ ط§ظ„ظ†ظ‘ظژط¨ظگظٹظ‘ظڈ ظٹظژظˆظ’ظ…ظژ ط§ظ„ظ’ظ‚ظگظٹظژط§ظ…ظژط©ظگ ظˆظژظ…ظژط¹ظژظ‡ظڈ ط§ظ„ط±ظ‘ظژط¬ظڈظ„ظژط§ظ†ظگ ظˆظژط£ظژظƒظ’ط«ظژط±ظڈ ظ…ظگظ†ظ’ ط°ظ„ظگظƒظژطŒ ظپظٹظڈط¯ظ’ط¹ظژظ‰ ظ‚ظژظˆظ’ظ…ظڈظ‡ظڈطŒ ظپظژظٹظڈظ‚ظژط§ظ„ظڈ: ظ‡ظژظ„ظ’ ط¨ظژظ„ظ‘ظژط؛ظژظƒظڈظ…ظ’ ظ‡ظژط°ظژط§طں ظپظژظٹظژظ‚ظڈظˆظ„ظڈظˆظ†ظژ: ظ„ظژط§ ظپظژظٹظڈظ‚ط§ظ„ظڈ ظ„ظژظ‡ظڈ: ظ‡ظژظ„ظ’ ط¨ظژظ„ظ‘ظژط؛ظ’طھظژ ظ‚ظژظˆظ’ظ…ظژظƒظژطں ظپظژظٹظژظ‚ظڈظˆظ„ظڈ: ظ†ظژط¹ظژظ…ظ’طŒ ظپظژظٹظڈظ‚ط§ظ„ظڈ: ظ…ظژظ†ظ’ ظٹظژط´ظ’ظ‡ظژط¯ظڈ ظ„ظژظƒظژطں ظپظژظٹظژظ‚ظڈظˆظ„ظڈ: ظ…ظڈط­ظژظ…ظ‘ظژط¯ظŒ ظˆظژط£ظڈظ…ظ‘ظژطھظڈظ‡ظڈطŒ ظپظژظٹظڈط¯ظ’ط¹ظژظ‰ ظ…ظڈط­ظژظ…ظ‘ظژط¯ظŒ ظˆظژط£ظڈظ…ظ‘ظژطھظڈظ‡ظڈطŒ ظپظژظٹظڈظ‚ظژط§ظ„ظڈ ظ„ظژظ‡ظڈظ…ظ’: ظ‡ظژظ„ظ’ ط¨ظژظ„ظ‘ظژط؛ظژ ظ‡ط°ظژط§ ظ‚ظژظˆظ’ظ…ظژظ‡ظڈطں ظپظژظٹظژظ‚ظڈظˆظ„ظڈظˆظ†ظژ: ظ†ظژط¹ظژظ…ظ’طŒ ظپظژظٹظڈظ‚ظژط§ظ„ظڈ: ظˆظژظ…ظژط§ ط¹ظگظ„ظ’ظ…ظڈظƒظڈظ…ظ’طں ظپظژظٹظژظ‚ظڈظˆظ„ظڈظˆظ†ظژ: ط¬ظژط§ط،ظژظ†ظژط§ ظ†ظژط¨ظگظٹظ‘ظڈظ†ظژط§طµظ„ظ‰ ط§ظ„ظ„ظ‡ ط¹ظ„ظٹظ‡ ظˆط³ظ„ظ‘ظ… ظپط£ط®ظ’ط¨ظژط±ظژظ†ظژط§ ط£ظژظ†ظ‘ظژ ط§ظ„ط±ظ‘ظڈط³ظڈظ„ظژ ظ‚ظژط¯ظ’ ط¨ظژظ„ظ‘ظژط؛ظڈظˆط§طŒ ظپظژط°ظ„ظگظƒ ظ‚ظژظˆظ’ظ„ظڈظ‡ظڈ ط¹ظژط²ظ‘ظژ ظˆظژط¬ظژظ„ظ‘ظژ:

﴿ظˆظژظƒظژط°ظژظ„ظگظƒظژ ط¬ظژط¹ظژظ„ظ’ظ†ظژظ€ظƒظڈظ…ظ’ ط£ظڈظ…ظ‘ظژط©ظ‹ ظˆظژط³ظژط·ظ‹ط§﴾

ظ‚ظژط§ظ„ظژ: ط¹ظژط¯ظ’ظ„ظ‹ط§

﴿ظˆظژظƒظژط°ظژظ„ظگظƒظژ ط¬ظژط¹ظژظ„ظ’ظ†ظژظ€ظƒظڈظ…ظ’ ط£ظڈظ…ظ‘ظژط©ظ‹ ظˆظژط³ظژط·ظ‹ط§ ظ„ظ‘ظگطھظژظƒظڈظˆظ†ظڈظˆط§ظ’ ط´ظڈظ‡ظژط¯ظژط¢ط،ظژ ط¹ظژظ„ظژظ‰ ط§ظ„ظ†ظ‘ظژط§ط³ظگ ظˆظژظٹظژظƒظڈظˆظ†ظژ ط§ظ„ط±ظ‘ظژط³ظڈظˆظ„ظڈ ط¹ظژظ„ظژظٹظ’ظƒظڈظ…ظ’ ط´ظژظ‡ظگظٹط¯ظ‹ط§﴾

(The Prophet would come on the Day of Resurrection with two or more people (his only following!), and his people would also be summoned and asked, `Has he (their Prophet) conveyed (the Message) to you' They would say, `No.' He would be asked, `Have you conveyed (the Message) to your people' He would say, `Yes.' He would be asked, `Who testifies for you' He would say, `Muhammad and his Ummah.' Muhammad and his Ummah would then be summoned and asked, `Has he conveyed (the Message) to his people' They would say, `Yes.' They would be asked, `Who told you that' They would say, `Our Prophet (Muhammad) came to us and told us that the Messengers have conveyed (their Messages). ')

Hence Allah's statement:

﴿ظˆظژظƒظژط°ظژظ„ظگظƒظژ ط¬ظژط¹ظژظ„ظ’ظ†ظژظ€ظƒظڈظ…ظ’ ط£ظڈظ…ظ‘ظژط©ظ‹ ظˆظژط³ظژط·ظ‹ط§﴾

(Thus We have made you a Wasat nation.)

He said, "(meaning) the `Adl,' (he then continued reciting the Ayah):

﴿ظˆظژظƒظژط°ظژظ„ظگظƒظژ ط¬ظژط¹ظژظ„ظ’ظ†ظژظ€ظƒظڈظ…ظ’ ط£ظڈظ…ظ‘ظژط©ظ‹ ظˆظژط³ظژط·ظ‹ط§ ظ„ظ‘ظگطھظژظƒظڈظˆظ†ظڈظˆط§ظ’ ط´ظڈظ‡ظژط¯ظژط¢ط،ظژ ط¹ظژظ„ظژظ‰ ط§ظ„ظ†ظ‘ظژط§ط³ظگ ظˆظژظٹظژظƒظڈظˆظ†ظژ ط§ظ„ط±ظ‘ظژط³ظڈظˆظ„ظڈ ط¹ظژظ„ظژظٹظ’ظƒظڈظ…ظ’ ط´ظژظ‡ظگظٹط¯ظ‹ط§﴾

(Thus We have made you, a just (and the best) nation, that you be witnesses over mankind and the Messenger (Muhammad ) be a witness over you.)''

Furthermore, Imam Ahmad reported that Abul-Aswad narrated: I came to Al-Madinah and found that an epidemic had broken out that caused many fatalities. I sat next to `Umar bin Al-Khattab once when a funeral procession started and the people praised the dead person. `Umar said, "Wajabat (it will be recorded as such), Wajabat!'' Then another funeral was brought forth and the people criticized the dead person. Again, `Umar said, "Wajabat.'' Abul-Aswad asked, "What is Wajabat, O Leader of the faithful'' He said, "I said just like Allah's Messenger had said:

آ«ط£ظژظٹظ‘ظڈظ…ظژط§ ظ…ظڈط³ظ’ظ„ظگظ…ظچ ط´ظژظ‡ظگط¯ظژ ظ„ظژظ‡ظڈ ط£ظژط±ظ’ط¨ظژط¹ظژط©ظŒ ط¨ظگط®ظژظٹظ’ط± ط£ظژط¯ظ’ط®ظژظ„ظژظ‡ظڈ ط§ظ„ظ„ظ‡ظڈ ط§ظ„ظ’ط¬ظژظ†ظ‘ظژظ€ظ€ط©آ»

ظ‚ظژط§ظ„ظژ: ظپظژظ‚ظڈظ„ظ’ظ†ظژط§ ظˆظژط«ظژظ„ظژط§ط«ظژط©ظŒطں ظ‚ظژط§ظ„ظژ: ظپظژظ‚ظژط§ظ„ظژ:

آ«ظˆظژط«ظژظ„ظژط§ط«ظژظ€ظ€ظ€ظ€ط©آ»

ظ‚ظژط§ظ„ظژ: ظپظژظ‚ظڈظ„ظ’ظ†ظژط§ ظˆظژط§ط«ظ’ظ†ظژط§ظ†ظگ: ظ‚ظژط§ظ„ظژ

آ«ظˆظژط§ط«ظ’ظ†ظژط§ظ†آ»

. ط«ظڈظ…ظ‘ظژ ظ„ظژظ…ظ’ ظ†ظژط³ظ’ط£ظژظ„ظ’ظ‡ظڈ ط¹ظژظ†ظگ ط§ظ„ظ’ظˆظژط§ط­ظگط¯ظگ.

(Any Muslim for whom four testify that he was righteous, then Allah will enter him into Paradise.' We said, `What about three' He said, `And three.' We said, `And two' He said, `And two.' We did not ask him about (the testimony) of one (believing) person.)''

This was also recorded by Al-Bukhari, At-Tirmidhi, and An-Nasa'i.