The New John Gill Exposition: Behold, a virgin shall conceive, and bear a son;
this is not to be understood of Hezekiah, the son of Ahaz, by his wife, as some Jewish writers interpret it; which interpretation Jarchi refutes, by observing that Hezekiah was nine years old when his father began to reign, and this being, as he says, the fourth year of his reign, he must be at this time thirteen years of age; in like manner, Aben Ezra and Kimchi object to it; and besides, his mother could not be called a "virgin": and for the same reason it cannot be understood of any other son of his either by his wife, as Kimchi thinks, or by some young woman; moreover, no other son of his was ever lord of Judea, as this Immanuel is represented to be, in [Isaiah 8:8] nor can it be interpreted of Isaiah's wife and son, as Aben Ezra and Jarchi think; since the prophet could never call her a "virgin", who had bore him children, one of which was now with him; nor indeed a "young woman", but rather "the prophetess", as in (Isaiah 8:3) nor was any son of his king of Judah, as this appears to be, in the place before cited: but the Messiah is here meant, who was to be born of a pure virgin; as the word here used signifies in all places where it is mentioned, as (Genesis 24:43) [Exodus 2:8] (Psalms 68:25) (Song of Solomon 1:3) [6] and even in (Proverbs 30:19) which is the instance the Jews give of the word being used of a woman corrupted; since it does not appear that the maid and the adulterous woman are one and the same person; and if they were, she might, though vitiated, be called a maid or virgin, from her own profession of herself, or as she appeared to others who knew her not, or as she was antecedent to her defilement; which is no unusual thing in Scripture.
And shall call his name Immanuel;
which is, by interpretation, "God with us", (Matthew 1:23) whence it appears that the Messiah is truly God, as well as truly man: the name is expressive of the union of the two natures, human and divine, in him; of his office as Mediator, who, being both God and man, is a middle person between both; of his converse with men on earth, and of his spiritual presence with his people. See (John 1:14) (1 Timothy 3:16) .