Hebrews 12:18–29 summarizes the lessons given through chapters 11 and 12. Those living under the new covenant have the advantage of looking to Christ, rather than to the law. The Old Testament was given through ominous signs, dire messages, fire, and sacrifice; it involved material things in a material world. God presented Himself as unapproachable, symbolic of His holiness. The New Covenant offers something better, and something beyond rituals and earthly needs. Also symbolically, Christ gives us an ability to approach God which the old covenant could not grant. While prior things can be changed and destroyed, the destiny offered to believers in Christ cannot. That is the ”kingdom that cannot be shaken,” and our worship for God ought to reflect reverence as a result.
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“Hebrews 12:28 Bibleref.com
28 Therefore, receiving a Kingdom that can’t be shaken, let’s have grace, through which we serve God acceptably, with reverence and awe,