Charles Ellicott Commentary Luke 2:4

"And Joseph also went up from Galilee, out of the city of Nazareth, into Judaea, to the city of David, which is called Bethlehem, because he was of the house and family of David;" — Luke 2:4 (ASV)

Unto the city of David, which is called Bethlehem.—St. Luke's way of speaking of the town agrees with that in John 7:42. It would appear to have been common. It had never ceased to glory in the fact that it had been David's city.

Of the house and lineage of David.—Others also—for example, Hillel, the great scribe—boasted of such a descent. What, on one hypothesis, was the special prerogative of Joseph was that the two lines of natural descent and inheritance—that through Nathan and that through Solomon—met in him. (See, however, Note on Luke 3:23.) It is possible that the two nearly synonymous words, “house” and “lineage,” may have been used to refer to this union.