John Calvin Commentary Luke 1:31

"And behold, thou shalt conceive in thy womb, and bring forth a son, and shalt call his name JESUS." — Luke 1:31 (ASV)

Behold, you will conceive in your womb. The angel adapts his words, first to Isaiah’s prophecy (Isaiah 7:14), and next to other passages of the Prophets, in order to affect more powerfully the mind of the virgin, for such prophecies were well known and highly esteemed among the godly. At the same time, it should be noted that the angel did not merely speak in private to the ear of the virgin, but brought glad tidings (εὐαγγέλιον), which were soon afterwards to be published throughout the whole world. It was not without the purpose of God that the agreement between ancient prophecies and the present message regarding the manifestation of Christ was so clearly pointed out. The word conceive is enough to refute the dream of Marcion and Manichaeus, for it is easy to gather from it that Mary brought forth not an ethereal body or phantom, but the fruit which she had previously conceived in her womb.

You shall call his name Jesus. The reason for the name is given by Matthew: for he shall save his people from their sins (Matthew 1:21). And so the name contains a promise of salvation and points out the purpose for which Christ was sent by the Father into the world, as He tells us that He came not to judge the world, but to save the world (John 12:47). Let us remember that this name was given to Him by the angel, not by the will of men, but by the command of God, so that our faith may have its foundation not on earth, but in heaven.

It is derived from the Hebrew word ישע (salvation), from which comes הושיע, which signifies to save. It is a waste of ingenuity to argue that it differs from the Hebrew name יהושוע (Jehoshua or Joshua). The Rabbis everywhere write the word Jesu; and they do this with evident malice, so that they may not give Christ an honorable name but, on the contrary, may insinuate that He is some false Jew. Their manner of writing it, accordingly, is of no more importance than the barking of a dog.

The objection that it is far beneath the dignity of the Son of God to have a name in common with others could equally apply to the name Christ, or Anointed. But the solution to both is easy. What was exhibited in shadow under the law is fully and actually manifested in the Son of God; or, what was then a figure is in Him a substance.

There is another objection of equally little weight. They assert that the name of Jesus is not worthy of veneration and awe—that at the name of Jesus every knee should bow (Philippians 2:9–10)—if it does not belong exclusively to the Son of God. For Paul does not attribute to Him a magical name, as if majesty resided in its very syllables, but his language simply means that Christ has received from the Father the highest authority, to which the whole world should submit. Let us then dismiss such imaginations and know that the name Jesus was given to Christ so that believers may be instructed to seek in Him what had formerly been shadowed out under the Law.