From the pen of Kim Riddlebarger:
The prophet Isaiah spoke of a future restoration of Israel in these terms: “But you, O Israel, my servant, Jacob, whom I have chosen, you descendants of Abraham my friend, I took you from the ends of the earth, from its farthest corners I called you. I said ‘You are my servant’; I have chosen you and have not rejected you” (41: 8– 9). The same promise was reiterated in the next chapter of Isaiah (42: 1– 7), when the Lord declared of his servant, “I will keep you and will make you to be a covenant for the people and a light for the Gentiles” ( v. 6). Isaiah continued to speak of this servant in chapters 44 (vv. 1– 2) and 45 (v. 4). Dispensationalists, who interpret such passages literally, assign the fulfillment of Isaiah’s prophecies to a future earthly millennium in which Israel will coexist with Gentiles under the reign of the Davidic king.[ 2] Is this how the New Testament interpreted these messianic prophecies regarding the servant of the Lord? Who is this servant of the Lord— the nation of Israel, or Jesus, Israel’s Messiah?
The Gospel writers interpreted these prophecies from Isaiah as fulfilled in the messianic mission of Jesus. As Jesus cast out demons and healed the sick, Matthew saw in this the fulfillment of Isaiah’s prophecies of a suffering servant who would take upon himself our infirmities and carry our diseases (Matt. 8: 17 with Isa. 53: 4). Luke spoke of both Israel and David as servants of God (Luke 1: 54, 69). Yet in Acts, Luke pointedly spoke of Jesus as the servant of God (Acts 3: 13). After Jesus’ crucifixion, God raised him from the dead so that people everywhere might be called to repentance (Acts 3: 26). Later on, when the Ethiopian eunuch read Isaiah 53: 7– 8 and asked Philip about whom this prophecy referred, Philip told him that this passage was about Jesus (Acts 8: 34– 35). But this is not all that is in view here.
The prophet Hosea quoted God as saying, “When Israel was a child, I loved him, and out of Egypt I called my son” (11: 1). But Matthew told us that Hosea’s prophecy was fulfilled when baby Jesus’ parents took him to Egypt for a time to protect him from Herod’s “slaughter of the innocents” (Matt. 2: 13– 18). Thus, Matthew, not the “spiritualizing amillenarian” centuries later, took a passage from Hosea which referred to Israel and told his readers that it was fulfilled in Jesus Christ.
According to many New Testament writers, Jesus was the true servant, the true Son, and the true Israel of God. Recall as well that Isaiah spoke of Israel and the descendants of Abraham as the people of God. It was through the seed of Abraham that the nations of the earth would be blessed. Therefore, even as Jesus was the true Israel, he was the true seed of Abraham.
Paul made this point in Galatians 3: 7– 8 when he said that “those who believe are children of Abraham. The Scripture foresaw that God would justify the Gentiles by faith, and announced the gospel in advance to Abraham: ‘All nations will be blessed through you.’” Paul’s words here are important for several reasons. First, they tell us that Abraham believed the same gospel that Paul preached to the Gentile Galatians. There has been only one plan of salvation and one gospel from the very beginning. This, of course, raises serious questions about the dispensational theory of distinct redemptive purposes for national Israel and the Gentiles. Paul also explained, “If you belong to Christ, then you are Abraham’s seed, and heirs according to the promise” (Gal. 3: 29). From the beginning of redemptive history, the true children of Abraham, whether Jews or Gentiles, will be heirs of God’s promise if they belong to Jesus Christ, the true seed of Abraham.
The ramifications for this on one’s millennial view should now be obvious. The New Testament writers claimed that Jesus was the true Israel of God and the fulfillment of Old Testament prophecies. So what remains of the dispensationalists’ case that these prophecies will yet be fulfilled in a future millennium? They vanish in Jesus Christ, who has fulfilled them.*
*Riddlebarger, Kim (2003-03-01). Case for Amillennialism, A: Understanding the End Times (Kindle Locations 1088-1103,1104-1117). Baker Publishing Group. Kindle Edition.