It is necessary or proper for someone to do something; it is someone's duty or obligation.
From Middle English 'bihouen,' derived from Old English 'behōfian.' The word originally expressed a sense of needfulness or obligation and has cognates in other Germanic languages meaning 'to have need of.'
Though rarely used today, 'it behoves you' still appears in formal writing and means 'it is your responsibility'—the word peaked in usage during the Victorian era when obligation and duty were favorite topics of literature and speeches.
Complete word intelligence in one call. Free tier — 50 lookups/day.