The message of the letter to the Hebrews is that Jesus Christ is the culmination of Jewish history, the end point to which the prophets of old had pointed and the perfect fulfillment of what had up to then been revealed only partially and sporadically.Bray, Gerald. God Is Love (pp. 724-725). Crossway
this is the book which establishes the finality of the gospel by asserting the supremacy of Christ-his supremacy as God's perfect word to man and man's perfect representative with God. More than any other New Testament book it deals with the ministry which our Lord is accomplishing on his people's behalf now.
The Epistle to the Hebrews