Asmodeus — Greek Asmodaios, from the Aramaic Ashmedai — is the most fully developed demonic figure in any book of the deuterocanonical Old Testament. He appears in the Book of Tobit, where he has fallen in love with the maiden Sarah and has killed each of her seven husbands on their wedding nights before the marriage could be consummated. Sarah's predicament is the dramatic motor of the second half of Tobit.
The deliverance comes through the archangel Raphael, sent by God in answer to the prayers of both Tobit and Sarah. Raphael, traveling as a companion to Tobias on his journey, instructs the young man on the proper rites — the burning of fish liver and heart on the bridal night — and the demon Asmodeus is driven away to the wilderness of Upper Egypt, where Raphael binds him. The marriage of Tobias and Sarah follows in joy.
Asmodeus is named only in Tobit and is not part of the Protestant canon. He is recognized in the Catholic, Orthodox, and Coptic traditions on the authority of Tobit, and the figure is referenced in some later Jewish texts (notably the Babylonian Talmud, Pesachim 110a, and the Testament of Solomon — though the latter is not canonical anywhere). For Christian readers, the theological value of the figure is not in his mythology but in what the narrative shows about the divine economy: that the prayers of the faithful are heard, that an archangel is sent to answer, and that the marriage covenant is defended against the destroyer who would unmake it.
Asmodeus killed seven husbands in the dark; he could not stand before the archangel sent in answer to a faithful prayer (Tobit 8:3).