This word occurs but once in the Authorized Version: "Let them learn first to show piety at home," better "toward their own household" or family. (1 Timothy 5:4) The choice of this word here instead of the more usual equivalents -of "godliness," "reverence," and the like, was probably determined by the special sense of pietas, as "erga parentes," i.e. toward parents.
PIETY
Meaning of PIETY in English
Smith's Bible English dictionary. Английский библейский словарь Смита. 2012