Clearly the immediate context of the verse in Isaiah 7 is Ahaz not being willing to ask for a sign to confirm the Lord's word to him in vs. 8, the shattering of Ephraim. Vs. 16 gives a timing indicator that squarely places the fulfilment of the sign the Lord gives, the virgin shall be with child..." in the generation of the prophecy.
From the context of Isah 7-9, 8:3 is clearly the fulfilment of the prophecy from 7:14.
However, it is also clear that Matthew, by the inspiration of the Holy Spirit, declares Jesus' birth to be the fulfilment of Isaiah 7:14.
Can someone give me the picture on how this is not a dual or near/far fulfilment?
I see how there are features that are not fulfilled literally in the birth of Isaiah's son Maher-shalal-hash-baz; his very name is a feature that does not square with the original prophecy. However, Isaiah's son's birth does square with 7:16 "For before the boy will know enough to refuse evil and choose good, the land whose two kings you dread will be forsaken."
It seems to me that Isaiah 7:14 has a partial fulfillment in the generation the prophecy was given as well as a complete literal fulfillment in the generation of the incarnation.