Wayne Grudem on the finality of the revelation of God in Christ

“God’s speech to us by His Son is the culmination of His speaking to mankind and is His greatest and final revelation to mankind in this period of redemptive history. The exceptional greatness of the revelation that comes through the Son, far exceeding any revelation in the old covenant, is emphasized again and again throughout chapters 1 and 2 of Hebrews. These facts all indicate that there is a finality to the revelation of God in Christ and that once this revelation has been completed, no more is to be expected.”
Wayne Grudem