Charles Ellicott Commentary Luke 1:35

"And the angel answered and said unto her, The Holy Spirit shall come upon thee, and the power of the Most High shall overshadow thee: wherefore also the holy thing which is begotten shall be called the Son of God." — Luke 1:35 (ASV)

The Holy Ghost shall come upon thee.—See Note on Luke 1:15. Here, however, the context would suggest to one familiar with the sacred writings another aspect of the Spirit’s work, as quickening the dead chaos into life (Genesis 1:2), as being the source of life to all creation (Psalms 104:30).

The power of the Highest shall overshadow thee.—The divine name is used in obvious harmony with the Son of the Highest in Luke 1:32.

Therefore also . . . shall be called the Son of God.—The words appear to rest the title, Son of God, rather on the supernatural birth than on the eternal pre-existence of the Son as the Word that was in the beginning with God and was God (John 1:1), and we may accept the fact that the message of the angel was in that respect a partial, not a complete, revelation of the mystery of the Incarnation. It gave a sufficient reason for the name which should be given to the Son of Mary, and more was not then required.