Text (taken from ESV)
18 For you have not come to what may be touched, a blazing fire and darkness and gloom and a tempest 19 and the sound of a trumpet and a voice whose words made the hearers beg that no further messages be spoken to them. 20 For they could not endure the order that was given, “If even a beast touches the mountain, it shall be stoned.” 21 Indeed, so terrifying was the sight that Moses said, “I tremble with fear.” 22 But you have come to Mount Zion and to the city of the living God, the heavenly Jerusalem, and to innumerable angels in festal gathering, 23 and to the assembly of the firstborn who are enrolled in heaven, and to God, the judge of all, and to the spirits of the righteous made perfect, 24 and to Jesus, the mediator of a new covenant, and to the sprinkled blood that speaks a better word than the blood of Abel.
25 See that you do not refuse him who is speaking. For if they did not escape when they refused him who warned them on earth, much less will we escape if we reject him who warns from heaven. 26 At that time his voice shook the earth, but now he has promised, “Yet once more I will shake not only the earth but also the heavens.” 27 This phrase, “Yet once more,” indicates the removal of things that are shaken—that is, things that have been made—in order that the things that cannot be shaken may remain. 28 Therefore let us be grateful for receiving a kingdom that cannot be shaken, and thus let us offer to God acceptable worship, with reverence and awe, 29 for our God is a consuming fire.
After the stern warning of he now encourages his readers, showing them the place and blessing they have come to. This he does first negatively (vv.18-21) and then positively (vv.22-24).
18-21 The author retells the story of the people of Israelat Mt. Sinai where they encountered God and heard of the covenant (what we now call the Mosaic covenant; Ex. 19-20). There was the voice (Ex. 19:16–24) and those who heard it begged that no further messages be spoken to them (Ex. 20:18–19). Even their great leader Moses said, “I tremble with fear.” (cf. Dt. 9:19).
22–24 But you have come is now the contrast the author draws. We have come to the city of the living God, the heavenly Jerusalem(cf. 11:10, 13-16). Peterson writes: “This is a vivid way of saying that we have secured the promised eternal inheritance through faith in Jesus and his work” (in loc.).
There we are going to meet innumerable angels in festal gathering and the assembly of the firstborn who are enrolled in heaven. But what group is the latter (Gr.: ekklēsiaprōtotokōn apogegrammenōn en ouranois)? This group is the same as in 2:12 (Lane, 468) which reads, “I will tell of your name to my brothers; in the midst of the congregation I will sing your praise” (Gr.: legōn apaggelō to onoma sou tois adelphois mou, en mesō ekklēsias humēsō se). Those individuals building the group are the saints redeemed by Christ – these are we!
They are the spirits of righteous men made perfect. This goes back to those who are made perfect “for ever by the one sacrifice of Jesus Christ (10:14)” (Peterson, in loc.).
God is the righteous judge and Christ the mediator of a new covenant, by whose blood “our hearts are sprinkled clean” from sin (10:22). The contrast between Abel’s blood and that of Chris’s is that the former cries out for vengeance but the latter speaks a better word namely that of forgiveness and acceptance.
25–27 It is still God who is speaking. He is the same God who spoke and who warned them on earth as He is now doing from heaven. Again an a fortiori argument (a loved literary device chosen by the author of Hebrews).
This is a similar argument as found in ch.2:1-3 where we read
Therefore we must pay much closer attention to what we have heard, lest we drift away from it. For since the message declared by angels proved to be reliable, and every transgression or disobedience received a just retribution, how shall we escape if we neglect such a great salvation?
Since Christ’s blood speaks a better word namely that of forgiveness and acceptance we must not refuse him who is speaking.
We already encountered the OT occasion of the giving of the law. The author now further comments that at that time his voice shook the earth (Ex. 19:18) and in Haggai 2:6 the Lord promised Yet once more I will shake not only the earth but also the heavens.” The author’s own comments on these are: This phrase, “Yet once more,” indicates the removal of things that are shaken—that is, things that have been made—in order that the things that cannot be shaken may remain.
28-29 The kingdom of God cannot be shaken is the force of the author’s argument here. The only proper way to response is to be grateful. Thanking God for His grace and His speaking to us is an act of service/worship (the Greek word here is latreuō and means to “serve, in our literature only of the carrying out of religious duties”; BDAG, 586) which is acceptableto God. But “Christian worship cannot be restricted to prayer and praise in a congregational context” (Peterson, in loc.). It is a life transforming encounter to hear God’s voice and an empowered life of gratitude is the result.
This act or life of service has to be done with reverence and awe. Why? The author says for our God is a consuming fire. This last phrase is taken from Deut. 4:24 where we read “For the Lord your God is a consuming fire, a jealous God.” Here (in the OT passage) the emphasis is on idolatry, and here in Hebrews also “the punitive aspect of God” is emphasized (Moffatt, 223).
Since we serve such a great God who has cleansed us and made us perfect (i.e., fitting) for worship and service let us with diligence and awe live the life to which we have been called.
Lane, William L. Hebrews. 9-13. Word Biblical Commentary, v. 47B. Dallas, Tex: Word Books, 1991.
Moffat, James. A Critical and Exegetical Commentary on the Epistle to the Hebrews. Edinburgh: Clark, 1948.
Peterson, David. “Hebrews.” New Bible Commentary : 21st Century Edition, 4th ed. Ed. D.A. Carson, et al. Leicester, England; Downers Grove, USA: Inter-Varsity Press, 1994.