Violence and justice are not antitheses of God, but he asks the Christian who has had their deserved violence placed on Christ to bear the violence of others. Injustice has been borne by the just one so the unjust could be justified. We don't know the hearts of others. We don't know where the Spirit will move and how it may touch the most wicked heart. It is not for us to decide the fate of others. It is for us to decide to lay down our lives, to forgive to the depths we've been forgiven, to love others even more than ourselves, and to trust God in his sovereignty and justice.
[Edit: I have just finished the book "Fight" by Preston Sprinkle, who gives a very interesting take on Revelation. I'm still researching it and verifying some things, but I'd recommend you check out his argument. You can find a summary in one of his points online here.]
[Edit 2: Tim Mackie (the guy from the Bible Project) has a great dialogue about Revelation that I find extremely compelling. I highy recommend checking out how he unpacks Revelation in context. You search for the dialogue towards the bottom of this page, or you can get it in the document below. I think I am officially on board with the non-violent interpretation of Revelation as it seems to make sense of John's structuring, the imagery, the context of the whole book of Revelation, the theme of Christ's sacrifice, etc. You can also find a great podcast interview with Mackie here, or you can listen to his six part podcast on the Day of the Lord here.]
[Edit 3: Greg Boyd has a series on Revelation called "Rescuing Revelation." He does a good job of exploring a more reasonable interpretation of Revelation than the modern notion that we find Hind gunships metaphorically represented in the book. The historic interpretation has tremendous explanatory power and considers that this book was written with the intent of being applicable to a people 2,000 years ago, and was written in the light of martyrdom for adhering to a Cruciform life, like our savior. Boyd follows the same general concept Mackie follows and I highly recommend you check him out. The sermon video below is the video I found to be the most pertinent. While I certainly disagree with Boyd about a number of important things, I think he nails the centrality of the cross and idea of the Kingdom.