If we study the history in the Old Testament, we will see that after God made the covenant with Abraham, His people had failure after failure and defeat after defeat. The blessing could not come, because the earth was full of rebellion against God. Therefore, God came to a man after His heart (1 Sam. 13:14), David, the son of Jesse, and made a covenant with him. Whereas the covenant with Abraham concerned the blessing, the covenant with David concerned the kingdom. God must have a kingdom, a realm, a sphere, on earth with His chosen race to exercise His administration under His full, divine authority. Without such a kingdom, God does not have a realm in which to accomplish His purpose. In order to be the blessing to His chosen people, God needs a kingdom, a realm, filled with His authority. Then in this administration He can come in to exercise whatever is on His heart to be the blessing promised to His chosen people.
It would be helpful at this point to consider the way the gospel is presented to us in the New Testament. It is presented first with these words: "Repent, for the kingdom of the heavens has drawn near" (Matt. 4:17). This indicates that the gospel is presented first not in the way of life, as in John, but in the way of the kingdom, as in Matthew. The reason for this is that there is the need of a kingdom, a realm, a sphere, for God to exercise Himself to give us His all-inclusive being. Even in John, the gospel of life, we are told that if we are not regenerated, we cannot enter into the kingdom of God (John 3:3, 5). There is the need of a kingdom so that God can exercise Himself to dispense Himself into us as our life blessing. Therefore, in the gospel, we receive Jesus Christ first not as life but as the King.
In Matthew we have the King-Savior; in Mark, the Slave-Savior; in Luke, the Man-Savior; and in John, the God-Savior. If we do not repent and receive the Lord as the King-Savior, we cannot have Him as the Slave-Savior, the Man-Savior, and the God-Savior.
We need to repent not only because we are sinful but because we are rebellious. We are even enemies of God. We need to repent of our rebellion. We sin because we are rebellious. If we did not rebel, we could not sin. Because we are rebels, we need to repent to receive Christ as our authority, as our Sovereign and King, that He may rule in us and over us in God's kingdom. This is the reason that in Matthew 1:1 Christ is presented first not as the son of Abraham for the blessing but as the son of David for the kingdom.
Once there is the kingdom, the kingdom becomes the realm, the sphere, for God to exercise Himself to bless us. We all like to receive the blessing, but we may not realize that the blessing requires a sphere of God's authority, a sphere under God's administration. Without such a sphere, there is no way for God to come in to bless us. If we are not under God's administration, receiving Him as our Sovereign, there is no way for Him to bless us. Therefore, in our experience as believers, our Savior, Jesus Christ, must first be the son of David for the kingdom and then the son of Abraham for the blessing.