جامع الترمذي

Narrated Abu Sa'eed: that about Allah's saying: Thus we have made you a Wasata nation (2:143) - the Prophet (ﷺ) said: "The meaning of Wasata is just."
[Abu 'Eisa said: This Hadith is [Hasan] Sahih.

(Another chain) From Abu Sa'eed who narrated that: "The Messenger of Allah (ﷺ) a said: 'Nuh will be called and it will be said: "Did you deliver (the Message)? "He will say: "Yes" and his people will be called and it will be said: "Did he call you?" They will say: "No warner came to us. No one came to us.' It will be said: "Who will testify for you?" So it is said: "Muhammad and his Ummah (community)." He (ﷺ) said: You will be brought to testify that he delivered (the Message) and that is His saying: Thus, we have made you a Wasata nation that you will be witnesses over mankind and the Messenger (Muhammad) will be a witness over you.' And Al-Wasat is "Just." (Sahih)
Abu 'Eisa said: This Hadith is Hasan Sahih.