Narrated Zaid bin Al-Arqam:
The Annwar said, "O Allah's Messenger! Every prophet has his own followers and we have followed you. So will you invoke Allah to let our followers be considered from us (as Ansar too)?" So he invoked Allah accordingly.
Narrated Anas:
I was in the company of Jabir bin `Abdullah on a journey and he used to serve me though he was older than I. Jarir said, "I saw the Ansar doing a thing (i.e. showing great reverence to the Prophet (ﷺ) ) for which I have vowed that whenever I meet any of them, I will serve him."
Anas b. Malik reported: I set out along with Jabrir b. 'Abdullah al-Bajali on a journey and he used to serve me. I said to him: Don't do that. Thereupon he said: I have seen Ansar doing this with Allah's Messenger (ﷺ). I swore by Allah whenever I accompany any one of the Ansar, I would serve him and Ibn Muthanni, and Ibn Bashshir made this addition in their narrations: Jarir was older than Anas, and Ibn Bashshir said: He was of a more advanced age as compared with Anas. Allah's Messenger (ﷺ) invoked blessings for the tribes of Ghifar and Aslam.