"We ought [to act piously] toward what relates to the god, since father Zeus regards all else as secondary."[1]
And elsewhere another [writer] says: "the only road toward happiness shown to mankind by god is the one through virtue. And the most valuable thing in it and, so to speak, the foundation of virtue as a whole is piety; for this alone adequately takes care of human affairs and becomes a good guide for humans with regard to divine matters."[2]