This speech is a great example of Imam Ali’s eleoquence and deep knowledge as well as his status as the great exemplar for the Sufis. The imporatnce of what he says here needs no comment and the seeds of the later doctrines of Walaya/Wilaya and all that it entails are to be found here.

Kumayl ibn Ziyād said: The Commander of the Faithful—Peace be upon him!—took my hand and brought me out to the cemetery (beyond the city walls). So when he had entered the desert he let out a great sigh, and then he said:
O Kumayl ibn Ziyād, these Hearts are containers: the best of them is the one that holds the most. So remember well what I am going to say to you!
The people are (divided into) three groups: a lordly (divinely inspired) Knower8; one seeking Knowing along the path of salvation; and the riffraff and rabble, the followers of every screaming voice, those who bend with every wind, who have not sought to be illuminated by the Light of Knowing and who have not had recourse to a solid Support.
O Kumayl, Knowing is better than possessions: Knowing protects you, but you must guard possessions. Possessions are diminished as they’re spent, but Knowing multiplies (or ‘purifies’) as it is shared. But whoever makes the possessions disappears as they do!
O Kumayl ibn Ziyād, the awareness/recognition (ma‘rifa) of Knowing is a Religion (dīn) by which (God) is worshipped and served:
through it the truly human being (insān) acquires willing obedience (to God) during their life (here), and a beautiful, wonderful state after their passing away. For Knowing is the Judge, and possessions are what is adjudged!
O Kumayl, those who accumulate possessions have perished, even while they are still alive. But the Knowers endure for all eternity: their particular-instances are lost, but their likenesses are found in the Hearts. O what Knowledge abounding there is right here!—and he pointed with his hand to his breast—if only I could reach those who are its (rightful) bearers.