Question: "Why is Jesus going to return on a white horse?"
Answer: In his vision of judgment upon the wicked, the apostle John tells us that Jesus is returning on a white horse: “Then I saw heaven opened, and behold, a white horse! The one sitting on it is called Faithful and True, and in righteousness he judges and makes war” (Revelation 19:11; see Psalm 45). Most Bible scholars are of the opinion that this passage is not referring to the Rapture, but rather to Jesus’ coming to earth with His saints at the end of the Tribulation.
The horse’s white color represents purity or victory (cf. Revelation 7:14-15), for this rider is holy and goes forth to be the triumphant conqueror. During ancient times, victorious Roman generals entered their conquered cities in chariots drawn by white horses. The entire setting of this verse implies victory over Christ’s enemies. As such, the word white indicates triumph, a successful war.
What a vivid contrast we see in Jesus’ return with all His angels (Matthew 25:31), as compared to His entry to Jerusalem upon a donkey (Matthew 21:7-9)! He is no longer riding a humble donkey. Jesus will return on a fiery white charger, bringing judgment, just as He had promised (Matthew 25:31-33).
Also by way of contrast, when He was on earth, Jesus was abandoned by His followers (Mark 14:50). Revelation 19 reveals the armies of heaven following Him in conquest. He is not returning to speak “gracious words” (Luke 4:22) but the words of righteous judgment (Isaiah 11:4). Jesus comes to rule with a rod of iron (Psalm 2:9). He is the King of Kings and the Lord of Lords (Revelation 17:14; Revelation 19:16).