The post is Isaiah 7, Nativity, and the Theotokos, written by Mark Olson, who speaks from an Orthodox perspective. He discusses quite accurately the difficulties involved with interpreting Isaiah 7 either from the Masoretic text or the LXX, the first based on language, and the second (or either) based on context. Let me extract one paragraph from his post:
But there is a problem for the modern western (protestant?) Christian who has decided the typological/allegorical hermeneutic is to be abandoned. For it seems if you do so, you need to abandon Isaiah 7 as a prophecy which points to Christ. Yet, noting that modern translators of texts such as the ESV, which primarily use the MT documents for their basis use the less proper translation term “virgin” over “unmarried/young girl” in this case. Why? Because they are Christian and the traditional Christian interpretation of this text is that it is in fact pointing to Christ and the Nativity. Yet that does violence to a consistent hermeneutical method.
I think Mark is right. If we stick with the historical-critical method, or even the historical-grammatical method, we really have no way to bridge the gap here. We can say that Matthew prophetically reapplies the passage when he quotes it, and we can give special privileges to early Christian interpreters–they get to take things out of context while we don’t–or we can ask whether the historical meaning taken in context is always the controlling factor.
As an aside, let me note that I don’t think the LXX is a translation of a different strand. The TDNT article on parthenos implies that the word may have overlapped the word ;almah more than is normally thought and thus it is neither a mistranslation, nor a different strand, but simply a case in which the semantic range of the two terms overlapped at the time of translation, but less so at the time of quotation (Matthew). In any case, I don’t think the translation issue will solve the problem completely, and this becomes even more difficult when one considers the syntax of Isaiah 7:14 which could quite easily be translated as “is pregnant” as well as “shall conceive.”
But laying all that aside we’re stuck with the likelihood that those who first heard Isaiah speak the words of Isaiah 7:14 would have understood it differently from the way in which Matthew applies it in Matthew 1:18-23.
I see this as an excellent case requiring typological interpretation, but also inviting us to do such typological interpretation within the bounds of church tradition, i.e. as part of a community. One of the great problems I see with allegorical or typological interpretation is that it lacks controls. My early inclination, during graduate school and for a time after, was to require the historical/contextual meaning as an anchor point for one’s typological understanding. To a certain extent, I think that is still good plan, but it doesn’t really cover everything.
First, the historical meaning doesn’t necessarily make much of a suggestion as to what typology might apply. One is stuck with a sort of subjective guess as to how far one has deviated from the historical meaning. Second, and as a result of the first, this idea really provides very little control. The easy answer from a western protestant perspective, is to try to drop typological and allegorical interpretation entirely. But if we do that we cut ourselves off from both much of the interpretation of the early church, and also most of the interpretation that scripture does of itself. Thus any allegorical interpretation we may do will be rootless.
If I might illustrate from another text, Hosea 11:1 as quoted in Matthew 2:15, I think there is an even greater contextual problem here, based on purely historical-grammatical or critical exegesis. Yet there is an excellent typological reason to connect the birth and mission of Jesus to the exodus. In fact, I think it is important to see the shaping of the story of Jesus from the exodus and then the exile and restoration if one is truly to understand redemption. I don’t think I’m terribly out of line with Christian tradition on that point, but what I want to underline here is that such a view involves a typological interpretation, not a contextual view of a text.
It seems likely to me here that Matthew, rather than interpreting a specific text loosely or contrary to context, is using a piece of phraseology from the exodus to draw the broader body of the exodus/redemption story into our understanding of the story of Jesus. To view it as a misappropriation of a phrase is a distinctly modern error, one of which I have been guilty in the past. Rather, Matthew takes advantage of the fact that his readers will know the broader story, and uses the one phrase as a tie-in to connect the stories together.