Chapter 16. Anger is the ebullition of the heart's blood .. Its three kind... (Book 2. The created world, and man's faculties and potential) (On the Orthodox Faith) (Damascene, John)

Anger is the ebullition of the heart's blood produced by bilious exhalation or turbidity. Anger is sometimes lust for vengeance. For when we are wronged or think that we are wronged, we are distressed, and there arises this mixture of desire and anger.

There are three forms of anger: rage, which the Greeks also call xolh or xoloj, uhnij and kotoj. When anger arises and begins to be roused, it is called rage or xolh or xoloj. Wrath again implies that the bile endures, that is to say, that the memory of the wrong abides: and indeed the Greek word for it, mhnij is derived from menein, and means what abides and is transferred to memory. Rancor, on the other hand, implies watching for a suitable moment for revenge, and the Greek word for it is kotoj from keisqai.

Anger further is the satellite of reason, the vindicator of desire. For when we long after anything and are opposed in our desire by someone, we are angered at that person, as though we had been wronged: and reason evidently deems that there are just grounds for displeasure in what has happened, in the case of those who, like us, have in the natural course of things to guard their own position.