Hebrews 1:3
The Son Is the Exact Imprint of God’s Nature
So God spoke long ago through the prophets, but now He has spoken to us in a definitive, decisive, and final way through His Son. But what is so definitive about the Son’s speaking? Why is the Son’s word God’s decisive and ultimate revelation about Himself—His nature, will, and way? Well, for this very reason: “He is the radiance of the glory of God and the exact imprint of His nature.” The Greek word for “exact imprint” is the same word for the impression left by a seal (Cockerill, NICNT, 94). The Apostle John said the same of the Son: “In the beginning was the Word, and the Word was with God, and the Word was God. He was in the beginning with God” (1:1-2). And the Apostle Paul agrees: “He is the image of the invisible God, the firstborn of all creation” (Colossians 1:15). Which is all to say that the Son is the definitive word of God BECAUSE as God’s only-begotten Son, HE IS GOD, the exact representation of the Father. What the Son says, the Father says, because the Son speaks what he hears the Father saying (John 5:30; 14:8-11). Moreover, having earlier said that the Father created the world through the Son (also John 1:3; Colossians 1:16), the writer of Hebrews now adds, “And he upholds the universe by the word of his power.” That is, not only did the Father create the world through the agency of the Son but He sustains it by that same agency and person.
What we have here is what we see throughout the New Testament, which is the advance of the New Testament upon the Old, making explicit in the New what was implicit in the Old, and that is, quite simply, Trinitarian theology. All three persons were in the beginning as the one God, but in some way which we cannot fully explain, the Father was the Original from whom the Son was begotten, the Holy Spirit proceeding from the Father and the Son. And because God is this mysterious and ineffable being who is three in one and one in three, the Son is able to reveal this God to us because he was sent from the Father for that very purpose. The prophets could not so reveal God. Oh, they could repeat what God told them to say, but only the Son can, not only repeat, but completely reveal, not only God’s words, but even His very nature to us. And the Son can do this because, as we said above, the Son is God. And for the same reason, the Son was the agent through which the Father created the world—because the Son is God.
The Son is that member of the Triune God whose task is mediation—the “through whom” member of the Trinity—through whom God created the world and through whom God definitively and ultimately reveals Himself.