The word in vv. 6-8 is actually the word of Christ, as quoted by Paul in Heb. 10:5-7. The prophecy in vv. 6-8 is one of the greatest revelations concerning the all-inclusive Christ in the commission that God committed to Christ in His first coming through incarnation, which was to put away the animal sacrifices of the old covenant and to establish Himself, in His body, as the sacrifice of the new covenant (see note Heb. 10:72b and note Heb. 10:91). This is to terminate God’s Old Testament economy and to initiate God’s New Testament economy, in which Christ replaces all the offerings as well as all things, all matters, and all persons (cf. Matt. 17:4-8; Col. 2:16-17; 3:10-11).
The prophecy in vv. 6-8 concerning Christ is the goal and destination of the revelation of Christ in Psalms 2, 8, 16, and 22—24. In this prophecy Christ comes through His incarnation to terminate God’s old economy and initiate God’s new economy, His New Testament economy, by replacing the animal sacrifices and establishing Himself as the unique sacrifice of the new covenant. As such a sacrifice, Christ is the factor that enacts God’s New Testament economy (Matt. 26:28) that He may be its centrality and universality for the producing and building up of the church as His organic Body, which will consummate in the New Jerusalem. Hence, Christ has changed the age for the consummating of God’s new creation out of God’s old creation (2 Cor. 5:17; Gal. 6:15). His changing of the age is greater than the creation of the universe mentioned in Gen. 1.