I Corinthians 15:28

Another key is found in the Corinthian passage itself — Paul's climactic statement that "the Son" is subjected "so that God may be all in all." Other Scriptures by this same Paul make it abundantly clear that Jesus Christ as God is "all in all" (e.g., Eph. 1:23, 4:10; Col. 3:11).

Of course, what this illustrates is that the apostle could not have been speaking of two divine persons in the literal sense. What he surely was speaking of was the Sonship of Jesus which will be subjected, that God may be "all in all." And many times in the New Testament "the Son" is spoken of in terms of "the Sonship." Oscar Cullmann agrees; for in his comment on 1 Corinthians 15:28, he has noted: "Here lies the key to all New Testament Christology. It is only meaningful to speak of the Son in view of God's revelatory action, not in view of his being [emphasis his]. But precisely for this reason, Father and Son are really one in this activity. Now we can say of the 'Son of God' what we said earlier of the Logos [the Word]: he is God as God reveals himself in redemptive action. The whole New Testament speaks of the redemptive action. Therefore the kingdom in which we live now, before the end, is the 'kingdom of the Son' (Col. 1.13).

Although it is the kingdom of God, it is also now known as the Son's kingdom. In this age we can receive the very Spirit of God, yet it is also called "the Spirit of His Son" (as well as "the Spirit of Christ"). Therefore, we should ponder thoughtfully Dr. Cullmann's following quote, for he is presenting the Biblical viewpoint: "The distinction between the Father and the Son has significance only from the point of view of Heilsgeschichte [German for "salvation history"]."

In future ages, there will be no need for the Son's "redemptive action"; there will be no need for the Sonship of God. In the new heavens and the new earth — after we are completely reconciled to our Creator—there will be no need for our God to live and die again as a Son on our behalf. At that time, the role of God as "Son" is to be subjected—"that God may be all in all."

However, until mankind is reconciled to the Creator in the new heavens and the new earth, man will need a "mediator" between himself and his God:

For there is one God, and one mediator between God and men, the man Christ Jesus. (1 Tim. 2:5)

This plain Scripture is but another key to the understanding of the Biblical concept of the Sonship of Jesus. The Greek word for "man" in the above verse is anthropos; and it literally means "a human being" (it is the very term from which the English has derived anthropology, "the study of man").

Thus according to this scripture, the only "mediator" which we have is the human being, Jesus of Nazareth—the time when God robed Himself with flesh as a Son, and walked among us "full of grace and truth." "This," says the apostle, "is our only mediator"! And the remainder of our present chapter will confirm that this mediator is: (1) A Son who received all power; (2) a Son who was over His own House; (3) a begotten Son—not an eternal Son.

Robert Brent Graves From: THE GOD OF TWO TESTAMENTS pp. 33, 34