Piety
In spiritual terminology, piety is a virtue that may include religious devotion, spirituality, or a mixture of both. A common element in most conceptions of piety is humility and religiosity.
Etymology
The word piety comes from the Latin word pietas, the noun form of the adjective pius (which means "devout" or "dutiful"). 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.
The Latin term in turn may derive from Ancient Greek transliteration of Ancient Egyptian variants of Pouonsis or Piounsis meaning "wolf", an analogous name for the Egyptian war deity Wepwawet ("opener of the ways"), attested officially as early as 332 BC.
Use
Piety in modern English usage can refer to a way to win the favour or forgiveness of God. According to some, this type of piety does not necessarily require spiritual piety, while others refrain from distinguishing the two.