Ibrahim ibne Alqamah and Aswad informed: “We went to Abu Ayyub AI-Ansari and said to him, ‘O Abu Ayyub, Allah honoured you by making His Messenger (s.a.w.a.) your guest. This is a virtue for you from Allah. So why did you join Ali and fight the Muslims who testified there is no god but Allah?
Abu Ayyub replied: I swear to Allah that the Messenger of Allah was in this house with me, just like you are right now. Ali was sitting to his right, I was sitting to his left, and Anas ibne Malik was standing in front of him.
Someone knocked at the door and the Prophet told Anas to see who it was. Anas came back and told the Prophet that Ammar ibne Yasir was at the door, at which point the Prophet told Anas to allow him to enter.
When Ammar came in, he greeted the Prophet (s.a.w.a.) and the Prophet (s.a.w.a.) welcomed Ammar.
Then the Prophet (s.a.w.a.) said – O Ammar! There will be a disaster in my nation after me and people will fight, kill, and disown each other. When you see that, hold on firmly to the man to my right (referring to Ali ibne Abi Talib (a.s.)). If all the people go one way but Ali goes the other way, stay with him and follow him.
O Ammar! Ali will not allow you to deviate from the path of guidance and he will not lead you to destruction.
O Ammar! Obeying Ali is obeying me, and obeying me is obeying Allah.’”
[T BASMR v 2 p 146] [T BEHAN v 38 p 37]