We have just considered the contrast, in Hebrews chapter 12, between Law and Gospel — under the figure of two mountains, Sinai and Zion. The gospel brings us to Mount Zion. It is not a place of fright, terror and dread, but rather of fulfillment and celebration, the fulfillment of all dreams and aspirations. But wait. God is no domesticated deity, either. He is not at our disposal, in need of our services, incomplete without our company, indifferent to our rejection.
“See to it that you do not refuse him who is speaking” (Heb. 12:25). If those who rejected God’s voice from earthly Sinai suffered terribly punishment, what fate must await those who reject God’s voice from Heaven itself? (v. 25). The divine voice at Sinai shook the earth (which nevertheless remained after the incident). The heavenly Voice will thunder once again at the End, quaking the entire universe, leaving nothing of the present created order in its wake, but only the eternal, permanent Kingdom of God (v. 26-28).
We are privileged to participate in this permanent Kingdom — God’s very priests, offering spiritual sacrifice with appropriate reverence and awe (v. 28). But remember: our God of salvation and mercy and redemption — when spurned and rejected throughout life — is finally a consuming fire (v.29; quoting Deut. 4:24).