"in fact hinting at the mystery of the Incarnation by pointing out a difficulty which only it could solve."
I believe this to be a major misunderstanding on multiple levels (which I will not go into at this time). To assert the idea of the incarnation being expressed by Messiah in relation to Psalm 110:1 even goes against the general outline of what Lewis was presenting about the role of the Psalms themselves. It does not fit with the scope of the Psalms, the Messianic/Davidic King (or any King of Israel for that matter), the suffering servant (as cited by Lewis from Psalm 22). This is later dogma pushing its way into eisegetical fraudulence. Here are a few other pieces I thought where interesting.
On Synagogue and Temple
The Old Testament Validity, Jesus, Psalm 110 and the Davidic, suffering, Messianic King“When I read the Bible as a boy I got the idea that the Temple of Jerusalem was related to the local synagogues very much as a great cathedral is related to the parish churches in a Christian country. In reality there is no such parallel. What happened in the synagogues was quite unlike what happened in the Temple. The synagogues were meetinghouses where the Law was read and where an address might be given-often by some distinguished visitor (as in Luke 4, 20 or Acts 13, 15). The Temple was the place of sacrifice, the place where the essential worship of Jahweh was enacted.”
"We are committed to it [the Old Testament] in principle by Our Lord Himself. On that famous journey to Emmaus He found fault with the two disciples for not believing what the prophets had said. They ought to have known from their Bibles that the Anointed One, when He came, would enter his glory through suffering. He then explained, from "Moses" (i.e. the Pentateuch) down, all the places in the Old Testament "concerning Himself" (Luke 24, 25-27). He clearly identified Himself with a figure often mentioned in the Scriptures; appropriated to Himself many passages where a modern scholar might see no such reference. In the predictions of His Own Passion which He had previously made to the disciples. He was obviously doing the same thing. He accepted-indeed He claimed to be-the second meaning of Scripture. We do not know-or anyway I do not know what all these passages were. We can be pretty sure about one of them. The Ethiopian eunuch who met Philip (Acts 8, 27-38) was reading Isaiah 53. He did not know whether in that passage the prophet was talking about himself or about someone else. Philip, in answering his question, "preached unto him Jesus". The answer, in fact, was "Isaiah is speaking of Jesus". We need have no doubt that Philip's authority for this interpretation was Our Lord…We can, again, be pretty sure, from the words on the cross (Mark 15, 34), that Our Lord identified Himself with the sufferer in Psalm 22. Or when He asked (Mark 12, 35, 36) how Christ could be both David's son and David's lord, He clearly identified Christ, and therefore Himself, with the "my Lord" of Psalm 110…how David can call Christ "my Lord" (Mark I2, 35-37), would lose its point unless it were addressed to those who took it for granted that the "my Lord" referred to in Psalm 110 was the Messiah, the regal and anointed deliverer who would subject the world to Israel. This method was accepted by all. The "scriptures" all had a "spiritual" or second sense. Even a gentile "Godfearer"' like the Ethiopian eunuch (Acts 8, 27-38) knew that the sacred books of Israel could not be understood without a guide, trained in the Judaic tradition, who could open the hidden meanings. Probably all instructed Jews in the first century saw references to the Messiah in most of those passages where Our Lord saw them; what was controversial was His identification of the Messianic King with another Old Testament figure and of both with Himself. Two figures meet us in the Psalms, that of the sufferer and that of the conquering and liberating one…The King was the successor of David, the coming Messiah. Our Lord identified Himself with both these characters. In principle, then, the allegorical way of reading the Psalms can claim the highest possible authority. But of course this does not mean that all the countless applications of it are fruitful, legitimate, or even rational. What we see when we think we are looking into the depths of Scripture may sometimes be only the reflection of our own silly faces. Many allegorical interpretations which were once popular seem to me, as perhaps to most moderns, to be strained, arbitrary and ridiculous. I think we may be sure that some of them really are; we ought to be much less sure that we know which. What seems strained-a mere triumph of perverse ingenuity-to one age, seems plain and obvious to another, so that our ancestors would often wonder how we could possibly miss what we wonder how they could have been silly-clever enough to find. And between different ages there is no impartial judge on earth, for no one stands outside the historical process; and of course no one is so completely enslaved to it as those who take our own age to be, not one more period, but a final and permanent platform from which we can see all other ages objectively."