Isaiah 6:6, “…one of the seraphim flew to me, having in his hand a burning coal that he had taken with tongs from the altar.”
Isaiah sees the Lord “high and lifted up” on the throne of His glory (6:1), and at this sight he—rightly—assumes that his life is forfeit…he is a sinful man and his eyes have seen the thrice holy YHWH. And yet, his life is spared—How? Because a seraph takes a coal “from the altar” and, by this coal, Isaiah’ “guilt is taken away” and his sin is “atoned for” (v.7). One pressing question is: from what altar was this coal taken?
Some would understand it to be the altar of incense standing before the Holy of Holies (since Isaiah’s vision is of the divine throne room which is the heavenly analogue to the earthly Holy of Holies). However, “without the shedding of blood, there is no forgiveness of sins” (Heb.9:22), and so it would be strange for the altar of incense—without any sacrifice involved—to be the means of atonement. Some would say that it is the altar of sacrifice, but the trouble here is that that altar is in the outer court and that does not fit with the context of Isaiah’s vision in the throne room. So, where might we see an altar of sacrifice *within* the throne room of YHWH?
I think a possible answer here is that the altar of sacrifice IS the throne itself. Yes—especially in light of NT revelation—the throne of God IS the altar of sacrifice and He Himself IS the sacrifice reigning from that Throne-Altar, by whose eternal self-giving (manifest definitively and temporally on Calvary) all sacrifice receives its efficacy.
John’s Gospel unites the high and lifted up Suffering Servant of Isaiah 52:13 with the high and lifted up YHWH of Is 6 (Jn 12:41ff), recognizing that the exalted throne of God’s glory IS the elevated cross (altar) of the Servant’s suffering. All of this comes together in the image of the slain and risen Lamb in the midst of the throne of God (Rev 5:6, 7:17, 22:1); the slain and risen Lamb whose presence on the throne reveals the throne of the universe to be the altar of Calvary, and the altar of Calvary to be the throne of the universe.