“Repent, or else I will come to you quickly and will fight against them with the sword of My mouth“
Repent, or else
The word “repent” is a strong command. This is sharp censure for imbibing false doctrine.
I will come to you quickly
“Quickly” has to do with the rapidity with which Jesus will come if the church at Pergamum does not repent. Jesus will go to war swiftly. He does not give leeway when it comes to false doctrine (2 Peter 2:1).
and will fight against them with the sword of My mouth
The word “fight” means to make war, to engage in open warfare (12:7; 13:4; 17:14). Jesus will make war on false doctrine. We do not often think of Jesus in terms of General Jesus. In this verse, He personally wields a sword of war. He is totally intolerant of tolerance.
Jesus is intolerant of tolerance.
Jesus’ sword will cut to the quick those who tolerate false beliefs. He will inflict a mortal wound on churches or organizations that leave the fundamentals of the faith. Confusion and sloppy thinking about truth is no excuse, He will judge them in any case.