The number four appears in the book of Revelation in association with the living creatures (Rev. Rev. 4:6+, Rev. 4:8+; Rev. 5:6+, Rev. 5:8+; Rev. 6:1+, Rev. 6:8+; Rev. 14:3+; Rev. 15:7+; Rev. 19:4+), the four horsemen of the first seven seals (Rev. Rev. 6:1-8+), the four angels (Rev. Rev. 7:1-2+) standing on the four corners of the earth (Rev. Rev. 7:1+) holding back the four winds of the earth (Rev. Rev. 7:1+), the four horns of the altar (Rev. Rev. 9:13+), the four angels bound at the great river Euphrates (Rev. Rev. 9:14+) who are released to kill a third of all mankind, and the four corners of the earth to which Satan travels to gather the final battle (Rev. Rev. 20:8+).
The symbolic meaning of the number four in the book of Revelation seems clear: it is the signature of the world or of global effect.1
Four . . . is the signature of the world . . . . Four is stamped every where on this the organized world. Thus, not to speak of the four elements, the four seasons, neither of which are recognized in Scripture, we have the four winds (Eze. Eze. 37:9; Mtt. Mat. 24:31; Rev. Rev. 7:1+); the four corners of the earth (Rev. Rev. 7:1+; Rev. 20:8+); the four living creatures, emblems of all creaturely life (Rev. Rev. 4:6+), and each of these with four faces and four wings (Eze. Eze. 1:5-6); the four beasts coming up from the sea, and representing the four great world-empires which in the providence of God should succeed one another (Dan. Dan. 7:3); the four metals composing the image which sets forth the same phases of empire (Dan. Dan. 2:32-33); the four Gospels, or the four-sided Gospel, in sign of its designation for all the world; the sheet tied at the four corners (Acts Acts 10:11; Acts 11:5); the four horns, the sum total of the forces of the world as arrayed against the Church (Zec. Zec. 1:18); the enumeration, wherever this is wished to be exhaustive of the inhabitants of the world by four, kindreds, tongues, peoples, and nations (Rev. Rev. 5:9+ cf. Rev. 7:9+; Rev. 10:11+; Rev. 11:9+; Rev. 14:6+; Rev. 17:15+). For other significant enumerations by four, see Eze. Eze. 14:21; John John 5:3; Rev. Rev. 6:8+. 2The first four of the seven seals, the four horsemen of the apocalypse (Rev. Rev. 6:1-8+), are each represented by a rider on a horse whose action has worldwide effects. The worldwide or global connotation of the number four derives from the directions of the compass (North, South, East, West, cf. Eze. Eze. 7:2) and may be why there are four living creatures which are around the throne (Rev. Rev. 4:6+) surrounding it in all four primary directions. This same directional emphasis is seen in the camp of Israel which camped around the tabernacle in the wilderness in these four primary directions (Num. Num. 2:1-34; Num. 23:10). This same arrangement is reflected in the tribal names associated with the twelve gates surrounding the New Jerusalem: 3 tribal names written on the gates in each of the four directions (Rev. Rev. 21:13+). The living creatures seen by John bear a striking resemblance to Ezekiels cherubim3 (Eze. Eze. 1:10; Eze. 10:14) which appear to support the chariot throne of God as it travels in any direction (Eze. Eze. 1:12; Eze. 10:16-17), yet with notable differences. Each of Ezekiels cherubim have four faces (a cherub or ox, a man, a lion, and an eagle) whereas Johns four living creatures each have a different face (a calf, a man, a lion, and an eagle). See Four Gospels.
The global emphasis of the number four is also seen in the four angels which kill a third of all mankind.4
2 [Richard Chenevix Trench, Commentary on the Epistles to the Seven Churches in Asia (Eugene, OR: Wipf and Stock Publishers, 1861), 63-64]. An exception to Trenchs comments regarding the four seasons may be found in the mention of seedtime (spring), harvest (fall), winter and summer in Gen. Gen. 8:22.
3 The word cherubim is the Hebrew equivalent to cherubs. The -im ending being the equivalent of our plural ending -s.