“the beating of an olive tree.” This refers to the biblical custom of beating the olive tree to get the olives off of it (Deut. 24:20). The beating got most of the olives but left some of them, and that is why this comparison is being used here in Isaiah 24:13. Isaiah 24 is about the Tribulation period that is described in the Book of Revelation, with its seal, trumpet, thunder, and vial judgments and the devastation of most of human and animal kind. Between the Tribulation and the Battle of Armageddon, “very few” people are left alive on earth. God is trying to make that point, so He says it plainly in Isaiah 24:6 (“very few are left”), and says it again in a pictorial way by comparing the people who are left on earth to the few olives that are left after the olive tree is beaten and also to the very little grain that is left (the gleanings) after the field is harvested.
Isaiah 24:13 is just one of the many places that the Bible says that very few people survive the Tribulation and Armageddon. Isaiah 13:12 says people will be scarcer than pure gold. Jeremiah 25:33 says the slain will be all over the earth. Jesus said that unless the days of the Tribulation and Armageddon were very short, “no flesh would have been saved” (Matt. 24:22). If you calculate the number of people who will be killed in the various judgments in Revelation, you get the same picture. But although there will be worldwide devastation, there is also hope, because the relatively small number of people who are left will praise Yahweh and sing songs to Him from all over the world (Isa. 24:14-16). In the Millennial Kingdom, people all over the world will worship Yahweh.
[For more on very few people being left alive on earth, see commentary on Isaiah 24:6. For more on the custom of beating the olive trees, see commentary on Deut. 24:20. For more on the worldwide devastation of the earth that will occur during the Great Tribulation, see commentary on Dan. 12:1. For more on people all over the world worshipping Yahweh in the Millennial Kingdom, see commentary on Zeph. 2:11. For more on the kingdom of Christ on earth, see Appendix 3, “Christ’s Future Kingdom on Earth”].