The first man, Adam, created by God in Gen. 1, failed to accomplish God's purpose for man. Psalm 8 then alludes, through prophecy, to another man, a man who would replace the first man and would fulfill God's purpose. This chapter tells us that this other man, the second man, who is Jesus, has come and has accomplished so much for the fulfilling of God's desire in man as revealed in Gen. 1:26, 28 and alluded to in Psa. 8:4-8. Hence, in whatever the first man, Adam, failed, the second man, Christ, succeeded, by replacing the first man.
This chapter is the fulfillment of the prophecies in Psa. 8 and Psa. 22 concerning the major steps taken by Christ, as a man, to fulfill God's purpose. In incarnation He partook of human nature (v. 14). In crucifixion He suffered death for everything (v. 9) and destroyed the devil (v. 14). In resurrection He brought forth many sons of God, His brothers, to form the church (vv. 10-12). In exaltation He was crowned with glory and honor. All these steps are the qualifications that qualify Him to be our High Priest (v. 17).