Therefore the Lord Himself will give you a sign: Behold, the virgin will be with child and give birth to a son, and will call Him Immanuel.
14. Therefore the Lord himself shall give you a sign. Ahaz had already refused the sign which the Lord offered to him, when the Prophet remonstrated against his rebellion and ingratitude; yet the Prophet declares that this will not prevent God from giving the sign which he had promised and appointed for the Jews. But what sign? Behold, a virgin shall conceive.
Here, I. God, by the prophet, makes a gracious offer to Ahaz, to confirm the foregoing predictions, and his faith in them, by such sign or miracle as he should choose (Isa 7:10, Isa 7:11): Ask thee a sign of the Lord thy God; See here the divine faithfulness and veracity. God tells us nothing but what he is able and ready to prove.
Commenting on Isaiah 7:10-16
Therefore the Lord himself shall give you a sign,.... Whether they would ask one or not; a sign both in heaven and earth, namely, the promised Messiah; who being the Lord from heaven, would take flesh of a virgin on earth; and who as man, being buried in the heart of the earth, would be raised from thence, and ascend up into heaven; and whose...