A.T. Robertson Commentary Luke 1:27

"to a virgin betrothed to a man whose name was Joseph, of the house of David; and the virgin`s name was Mary." — Luke 1:27 (ASV)

Betrothed (εμνηστευμενην). Perfect passive participle. Betrothal usually lasted a year and unfaithfulness on the part of the bride was punished with death (Deuteronomy 23:24f.).