Chapter 19 opens with a colourful contrast leading on from the end of Chapter 18. It, in itself, is a contrast with the fall of Babylon, its judgement, verses the bride of the Lamb, and the celebration associated with a wedding.
Halleluyah "Praise Yahweh" is a Jewish term that the original audience would have recognised. More than that, the Greek-Roman world would have also understood its meaning. This contrasts with the mourning we saw in chapter 18. Now we hear cheering, a celebration. This prompts us with a choice: Which do we want to be a part of? The world, which will fall, or the Lamb, and to be part of Christ's bride? To help with this choice we see that salvation, glory, and power all belong to God. We all know that a wedding and the associated banquet is a joyous occasion, (Isaiah 25:6), but is also a symbol of God's promises.
"Blessed are those who..." is the same language we see in the beatitudes (Matthew 5). This encourages God's people to preserve. White Linen shows us that we are to prepare ourselves to be the bride of Christ. White, pure, righteous, not something new or hard to see through the wedding metaphor, but what's the preparation we need to do? This refers to our acts, what we do in response to God's grace. Social justice, the rejection of idolatry, faithful witness, and taking part in the generous praise and thanksgiving to God. These are all topics highlighted throughout the Book of Revelation.
The Angel's words, acting as God, confuses John in this vision. The Angel tells us to only worship God. Often used to counteract the Catholic practice of worshiping saints and Mary. We, acting as prophets, are fellow servants who are only to worship the one true living God.
Now, in verse 11, we are presented with the rider Faithful and True upon a white horse. Contrasted perhaps with the four horsemen from the seals showing conquest, war, famine, and death. The white horse is a symbol of a strong military leader similar to a Roman General overseeing his troops. This is clearly Jesus, the Messiah, the Christ! It reminds us that God is the one that makes war, not man. The Jewish had the idea that the Messiah would wage war against Rome, their oppressors, and reestablish a physical kingdom on earth, yet here we see the Messiah striking with His mouth (Isaiah 11:4), showing us that the Messiah provides a different salvation, an eternal salvation.
The many crowns and the title "King of kings" (the same title used for the ruler of the Parthians), showing the audience Jesus's power. The red eyes show His divinity and fury. The result is that the leaders of Satan's army, the beast and the false prophet, are thrown into the fiery lake of burning sulfur (mentioned previously as being a reference to Genesis 19:24), and is a contrast to the sea of glass we see in the Throne Room.
What we have here is the Holy War. Jesus is all-powerful, yet, while we have this image of a war, there is no battle. Rather, this is a call to God's people to prepare for the victory! We are to prepare, to prepare with justice and mercy, to establish the kingdom on earth. We know that this won't be complete until He comes again, but we are to prepare with urgency! We learn that we won't win all the earthly battles we face, but we can see and be encouraged in hope that the holy war has already been won. That the justice we receive from Jesus is all that matters and that it will be eternal.