Hebrews 12:25-29

See that you do not refuse Him who is speaking. For if they did not escape when they refused Him who spoke on earth, much less shall we escape if we turn away from Him who speaks from heaven. At that time His voice shook the earth, but now He has given us a promise, saying, “Yet once more I will shake not only the earth but also heaven.” And this statement, “Yet once more,” signifies the removal of those things that can be shaken, things that are created, so that only those things that cannot be shaken will remain. Therefore, since we are receiving a kingdom that cannot be moved, let us be gracious, by which we may serve God acceptably with reverence and godly fear. For our God is a consuming fire.