Imam 'Adham's Restraint

The example that best represents Imam Abu Hanifa's restraint is when a layman came to Abu Hanifa and asked him a question regarding a fatwa of Hasan Al Basri. Abu Hanifa stated, “Hasan erred.” So the man said to Abu Hanifa, “You say that Hasan erred, son of a *****.”
Abu Hanifa did not redden or get upset. He said,“By Allah, Hasan erred and Abullah ibn Mas’ud was correct.”

[source: The Four Imams: Their Lives, Works, and their Schools of Thought, Muhammad Abu Zahra’s book.]