Piety is a virtue which may include religious devotion or spirituality. A common element in most conceptions of piety is a duty of respect. In a religious context, piety may be expressed through pious activities or devotions, which may vary among countries and cultures.
The word piety comes from the Latin word pietas, the noun form of the adjective pius (which means "devout" or "dutiful"). English literature scholar Alan Jacobs has written about the origins and early meaning of the term:
It is not, in its origin, a Christian word. The Roman poet Virgil calls his hero pius Aeneas, says that he is a pietāte virum, but we might well mislead readers were we to say “pious Aeneas” or a “pious man.” For his character is unmarked by the smarmy religiosity we typically associate with the word “pious.” Aeneas is devoted to his mission, is faithful to the call of the gods on his life. He is willing to sacrifice his own interests to those greater interests, especially to the founding of the great city of Rome. He binds his will and his heart to that task. This is what it means to be pius.
Pietas in traditional Latin usage expressed a complex, highly valued Roman virtue; a man with pietas respected his responsibilities to gods, country, parents, and kin. In its strictest sense it was the sort of love a son ought to have for his father. Aeneas's consistent epithet in Virgil and other Latin authors is pius, a term which connotes reverence toward the gods and familial dutifulness. At the fall of Troy, Aeneas carries to safety his father, the lame Anchises, and the Lares and Penates, the statues of the household gods.
In addressing whether children have an obligation to provide support for their parents, Aquinas quotes, Cicero, "..."piety gives both duty and homage": "duty" referring to service, and "homage" to reverence or honor." Filial piety is central to Confucian ethics; reverence for parents is considered in Chinese ethics the prime virtue and the basis of all right human relations.