Synopsis of the Books of the Bible, by John Nelson Darby, [1857-62], at sacred-texts.com
Isaiah Chapter 49
The Messiah is brought in, for it is He who delivers. But it is a question apart, so to say. The subject of Christ, and of the people's guilt with respect to Him, begins with chapter 49, which, with the following to the end of chapter 57, forms a whole; and, if one may venture to say so, Christ takes the place of Israel as the true servant of God. As He declared. "I am the true vine." [See Note #1] This makes an apparent difficulty, but gives the true sense of chapter 49. Israel is the vessel of the glory of God on the earth, and the Spirit of prophecy in Israel calls on the isles of the Gentiles to hearken, as being thus chosen of Jehovah. "Thou art my servant, O Israel, in whom I will be glorified" (Isa 49:3). Then Christ, by this same prophetic Spirit, says, "then have I laboured in vain." For we know that Israel rejected Him. Verse 5 (Isa 49:5) is the answer. He shall be glorious. It would be a light thing to restore the remnant of Israel. He shall be the salvation of Jehovah unto the ends of the earth. Here we find a principle that is applicable to the work of Christ, even in the days of the gospel. But for the fulfilment of the counsels of God the succeeding Verses carry us on to the millennium. Verse 7 (Isa 49:7), Christ is exalted. Verse 8 (Isa 49:8), He is given for a covenant of the people (Israel) to secure the blessing of the land of Canaan, and the long desolate inheritance, and then the deliverance of the captives. At length God has comforted His people. Zion, apparently forsaken, must confess that Jehovah's faithfulness is greater than of a mother to her sucking child. Her destroyers are gone, her children flock in crowds to her and replenish her waste places, which regorge with an unlooked-for multitude before the eyes of the astonished mother, long time desolate. Kings shall be her nursing fathers, and shall bow down to her. And although she has been the captive of the mighty, she shall be delivered, and her oppressors trodden under foot. And all flesh shall know that Jehovah is her Saviour. This is the result in grace of the introduction of the true Servant.
Note #1
So, I doubt not, in Matthew, "I have called my Son out of Egypt." Christ replaces the first Adam before God, though blessing in that new position many of his children. He takes the place of Israel also, though blessing the remnant and making it the nation.