5 We have next to examine the argument which we bear continually coming from the lips of the common people, and find embedded in popular conviction, that sacrifices are offered to the gods of heaven for this purpose, that they may lay aside their anger and passions, and may be restored to a calm and placid tranquillity, the indignation of their fiery spirits being assuaged. And if we remember the definition which we should always bear steadily in mind, that all agitating feelings are unknown to the gods, the consequence is, a belief that the gods are never angry; nay, rather, that no passion is further from them than that which, approaching most nearly to the spirit of wild beasts and savage creatures, agitates those who suffer it with tempestuous feelings, and brings them into danger of destruction.
For whatever is harassed by any kind of disturbance, is, it is clear, capable of suffering, and frail; that which has been subjected to suffering and frailty must be mortal; but anger harasses and destroys those who are subject to it: therefore that should be called mortal which has been made subject to the emotions of anger. But yet we know that the gods should be never-dying, and should possess an immortal nature; and if this is clear and certain, anger has been separated far from them and from their state. On no ground, then, is it fitting to wish to appease that in the gods above which you see cannot suit their blessed state.
Source: Against the Heathen (New Advent)