This is a further explanation of the world-ruling empires, showing national characteristics, but this time designed into animals of the same four kingdoms that appear in Daniel 2. Instead of being metals—gold, silver, brass, iron—now we have animals, indicating national characteristics of those four kingdoms, symbolized by the lion, the bear, the leopard, and the beast that was diverse from all the others.
The important thing to note here is that this illustration in Daniel 7 is a parallel of the image seen by Nebuchadnezzar in Daniel 2. This illustration in Daniel 7 confirms that the legs of iron of the Daniel 2 image and the fourth beast of Daniel 7 both exist at Christ's return, fight against Him, and are defeated. So even as the feet and toes of the Daniel 2 image will be at the time of the end, so will this diverse beast. They are one and the same.
John W. Ritenbaugh
Where Is the Beast? (Part 1)
Other Forerunner Commentary entries containing Daniel 7:18:
1 Thessalonians 4:17