For piety towards the gods know that the most important thing is this: to have right opinions about them—that they exist, and that they govern the universe well and justly—and to have set yourself to obey them, and to give way to all that happens, following events with a free will, in the belief that they are fulfilled by the highest mind. For thus you will never blame the gods, nor accuse them of neglecting you. But this you cannot achieve, unless you apply your conception of good and evil to those things only which are in our power, and not to those which are out of our power. For if you apply your notion of good or evil to the latter, then, as soon as you fail to get what you will to get or fail to avoid what you will to avoid, you will be bound to blame and hate those you hold responsible. For every living creature has a natural tendency to avoid and shun what seems harmful and all that causes it, and to pursue and admire what is helpful and all that causes it. It is not possible then for one who thinks he is harmed to take pleasure in what he thinks is the author of the harm, any more than to take pleasure in the harm itself. That is why a father is reviled by his son, when he does not give his son a share of what the son regards as good things; thus Polynices and Eteocles were set at enmity with one another by thinking that a king’s throne was a good thing. That is why the farmer, and the sailor, and the merchant, and those who lose wife or children revile the gods. For men’s religion is bound up with their interest. Therefore he who makes it his concern rightly to direct his will to get and his will to avoid, is thereby making piety his concern. But it is proper on each occasion to make libation and sacrifice and to offer first-fruits according to the custom of our fathers, with purity and not in slovenly or careless fashion, without meanness and without extravagance.