Piety, in the Pagan sense, is described as the “defining quality of a human being who acted deliberately in accordance with both the divine will and the civil law.”
Piety encompasses fidelity, honor, discipline, as well as reverence. For example, the Romans were scrupulous in guarding the right relationship between themselves and the Gods. Their religious ceremonies involved preparation and a strict adherence to the order of each rite. Honor for the Romans came in listening to the Gods through the taking of the omen. Discipline was in the careful preparation before each rite.
Although the Germanic peoples did not have “piety” as virtue, they stressed that no one should compromise their relations to the Gods. For example, the Saxons regarded their kings to be mediators between the Gods and the tribe. If the King brought bad luck, they disposed him.
For me, piety means taking the Gods seriously. They are neither cosmic bellhops always getting things for us, nor our personal buddies always ready to hang out with us. Piety does not mean making things up as you go long. It does not mean worshiping at your convenience. To be pious is to be mindful of the right relationship between humans and the Gods.