Musar for Nedarim 44:13

Whoever has a brain in his head must flee this evil trait as one flees fire. For he knows in his soul clearly that because of this evil trait he will certainly emerge "liable" on the day of judgment, as it is known, that one who has an abundance of sins [over merits] is in the category of rasha [wicked]. And Chazal have said (Nedarim 22b): "If one is prone to anger, it is known that his sins are more than his merits, as it is written (Mishlei 29:22): 'And the man of wrath is abundant in offense [pesha].'" As to "pesha" being written, which is rebellion, and worse than meizid [malice], this is because at the time of anger, Torah and mitzvoth are entirely meaningless to him. As Chazal have said: "If one gets angry, even the Shechinah is meaningless to him." And our Rabbis of blessed memory have said: "If one tears his garments in his anger or breaks his vessels in his anger or scatters his money in his anger, let him be as an idolator in your eyes. Where is this written? (Psalms 81:10): 'Let there not be a foreign god within you.' What is the foreign god within a man's body? The yetzer hara of anger."