The writer shifted again from exposition to exhortation. The hook word "speak"(Gr. lalountiand lalounta) in verses 24 and 25 ties the two sections together.
12:25 The One speaking probably refers to God. "Him who warned them on earth"probably refers to God when He spoke from Mt. Sinai. The contrast is not between the persons who spoke but between the places from which God spoke (cf. v. 26). It would have been specially impressive to Jewish Christians. The present warning came from God in heaven and dealt with failure to continue to cleave to His Son (cf. 1:1-2; 2:2-3).
12:26-27 God's voice shook the earth at Mt. Sinai (Exod. 19:18; Judg. 5:4-5; Ps. 68:8; 77:18; 114:4, 7). It will shake the earth and the heavens at the end of the Millennium. That shaking will lead to the creation of new heavens and a new earth that will remain (Ps. 95:9-11; Hag. 2:6; Rev. 21:1).
"The shaking' is a metaphor for the judgment of God executed in history, as in the case of the fall of Babylon announced in Isa 13:1-22."428
12:28-29 Our kingdom is eternal. Our motive should be gratitude. Our activity should be the service of God. Our attitude toward Him should be reverence and awe in view of His ability to judge the unfaithful (cf. 1 Cor. 3:14-15).
"As a consuming fire, God purifies all that is unworthy and unacceptable in those who serve Him and all that is unfit to abide in His presence."429
Many readers of Hebrews associate the figure of God consuming with His judging unbelievers in hell, but this figure also occurs in the Old Testament with reference to His judging His people (cf. Exod. 24:17; Lev. 10:2; Num. 16:35; Deut. 4:24; 1 Cor. 3:15).
The reference to fire in verse 29 completes an inclusiobegun with another mention of fire in verse 18. The whole section that these references to fire enclose deals with how important it is to respond properly to God.
"The warning proper is found in 12:25-29. The readers are called to heed Yahweh, for an eschatological shaking is coming in which the earthly material order will pass away, leaving only an eternal kingdom. The faithful readers who endure will have a part in the eschatological kingdom--the millennium and the New Jerusalem as companions' of Jesus, the Messiah-King (1:9, 13-14). This kingdom will become an eternal kingdom. . . .
"All five warnings in the epistle have a positive thrust and a negative impetus. . . . Disobedience to God and His Word will result in a forfeiting of eschatological rewards; obedience to God and His Word will result in a gaining of eschatological rewards."430
Warren Wiersbe pointed out that this chapter contains three resources that encourage and enable us to run the Christian race with endurance. They are the example of Jesus (vv. 1-4), the assurance of the Father's love (vv. 5-13), and the enablement of God's grace (vv. 14-29).431
