Matthew 1:23

ἡ παρθένος ἐν γαστρὶ ἕξει. Not a Virgin as A.V. but the Virgin: so also the Hebrew, which differs from this quotation only in having the singular ‘she shall call.’ The citation agrees with the LXX. where however the reading varies between ἕξει and λήψεται and between καλέσεις and καλέσουσιν. See Isaiah 7:14.

The historical crisis was this, Ahaz is alarmed by the threatened invasion of Pekah and Rezin—the confederate kings of Samaria and Damascus. Isaiah reassures Ahaz, who hypocritically refuses to ask for a sign. Yet a sign is given. She, who is now unmarried, shall bear a son, probably a scion of the royal house of David; he shall be called Emmanuel, and before he arrives at years of discretion the deliverance shall come, though a heavier distress is at hand.
The prophecy is distinctly Messianic, but the sign in Isaiah is not concerned with the manner of the child’s birth, but with the name, and the deliverance which should happen in his infancy. Therefore, the weight of the reference is to the name ‘Emmanuel’ and to the true Son of David, whose birth was the sign of His people’s deliverance.

μεθερμηνευόμενον, a late word (Polyb. and Diod. Sic.). Cp. τοὺς καλουμένους ἐξτραορδιναρίους ὃ μεθερμηνευόμενον ἐπιλέκτους δηλοῖ. Polyb. VI. 26. 6. The explanation would not of course appear in the original Aramaic gospel.