And hath raised up an horn of salvation for us in the house of his servant David;
And hath raised up an horn of salvation for us - that is, a 'strength of salvation,' or 'a mighty salvation;' meaning the Saviour Himself, whom Simeon in his song calls "Thy Salvation" (Luke 2:30). The metaphor is taken from those animals whose strength lies in their horns, and was familiar in the Psalmody of the agricultural Jews, (Psalms 132:17; Psalms 75:10; Psalms 18:2, etc.)
In the house of his servant David. This shows that Mary must have been of the royal line, independent of Joseph-of whom Zacharias could not know that after this he would recognize his legal connection with Mary. The Davidic genealogy of the Messiah, as it was one of the most prominent of His predicted characteristics, and one by which the Jews were warranted and prepared to test the pretensions of any claimant of that office who should arise, so it is here emphatically sung of as fulfilled in the unborn Offspring of the blessed Virgin.