Abu Huraira (Radhi-Allahu ‘anhu) reported:

I heard Allah’s Messenger (salAllahu alayhi wa sallam) as saying: One is not strong because of one’s wrestling skillfully.

They said: Allah’s Messenger (salAllahu alayhi wa sallam), then who is strong?

He (salAllahu alayhi wa sallam) said: He who controls his anger when he is in a fit of rage.

[Sahih Muslim – Book 032: Hadith 6314]