"With these wonderful words John introduces the New Testament church to Old Testament understanding. For the first time in the book of Revelation, here at the very beginning, he is bringing the Old Testament literal types and shadows over into the New Testament fulfillment. The Old Testament was all about natural, physical, earthly types and shadows of kingship and priesthood. Their kings and priests sat on physical thrones and offered animal sacrifices upon brazen altars in temples made with hands. But now John is raising this kingship and priesthood into a higher, spiritual dimension and announces to the saints that Christ now “hath made us kings and priests unto God and His Father.” With this simple beginning John does what we have seen him do constantly throughout the book of Revelation — refer to Old Testament terminology within the context of New Testament spiritual reality! And then, shortly, we are shown another scene."
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"And…the four Living Creatures and the four and twenty Elders…sung a new song, saying, Thou art worthy to take the book, and to open the seals thereof: for Thou wast slain, and hast redeemed us to God by Thy blood out of every kindred, and tongue, and people, and nation; and hast made us unto our God KINGS AND PRIESTS: and we shall reign on the earth” (Rev. 5:8-10)