Antiphona ad Magnificat

From Luke 1:32-33, the Angel Gabriel's announcement to Mary: 'Dabit illi Dominus Deus sedem David patris ejus' (the Lord God shall give unto him the throne of David his father). Christ's kingship is not merely spiritual but fulfills the Davidic covenant - He inherits the historical throne of Israel. The phrase 'regnabit in domo Jacob in aeternum' (he shall reign in the house of Jacob forever) extends this reign beyond Israel's earthly duration to eternity. The closing 'regni ejus non erit finis' (of his kingdom there shall be no end) distinguishes Christ's realm from every terrestrial empire. At First Vespers, this antiphon roots the feast in the Annunciation: Mary received the first proclamation of Christ's kingship.