Saad bin T’areef, from Asbagh bin Nobatah, from Salman Al-Faresi, who said:
I heard the MESSENGER OF ALLAH (SWT) tell Muhajerin and Ansar, “O Muhajerin and Ansar, should I guide you to someone? If you follow this person you will never get lost after me.”
They replied, “Yes, O MESSENGER OF ALLAH (SWT).”
The PROPHET (SAWW) said, “This is ALI (ASWS), my brother, my successor, my minister, my heir, my caliph, and your Imam. Love him because of your love for me, and honour him because of your honour for me. Jibraeel ordered me to tell you what I just said to you.”
(Amaali of Sadouq 386; Amaali of Tousi 1:226)