Hebrews 12:25-29

Watch out that you do not refuse the one who is speaking! For if those did not escape when they refused the one who warned them on earth, much less will we escape, if we reject the one who warns from heaven, whose voice shook the earth at that time, but now he has promised, saying, “Yet once more I will shake not only the earth but also heaven.” Now the phrase “yet once more” indicates the removal of what is shaken, namely, things that have been created, in order that the things that are not shaken may remain. Therefore, since we are receiving an unshakable kingdom, let us be thankful, through which let us serve God acceptably, with awe and reverence. For indeed our God is a consuming fire.