According to Howard Clarke, in this verse, Isaiah seems to be explicitly referring to a son of the Judean King Ahaz (ca. 735-15) rather than to his mother as Matthew understands it.
Judaism and the Hebrew Bible
Judaism reads the verse in Isaiah 7:14 as:
"Therefore the Lord Himself shall give you a sign: behold, the young woman [ha-almah] shall conceive, and bear a son, and shall call his name Immanu-el".Judaism affirms that [ha-almah] ("young woman") does not refer to a virgin and that had the Tanakh intended to refer to such, the specific Hebrew word for virgin [bethulah] would have been used. This view is often disputed by Christians (see below), and has been a point of contention between Jews and Christians since the formation of the modern Church. Jerome, in 383 CE, wrote in "Adversus Helvidium" that Helvidius misunderstood just this same point of confusion between the Greek and the Hebrew.