Or else I will come unto thee quickly. On the word quickly, See Barnes on "Re 1:1".

The meaning here is, that he would come against them in judgment, or to punish them.

And will fight against them. Against the Nicolaitanes. He would come against the church for tolerating them, but his opposition would be principally directed against the Nicolaitanes themselves. The church would excite his displeasure by retaining them in its bosom, but it was in its power to save them from destruction. If the church would repent, or if it would separate itself from the evil, then the Saviour would not come against them. If this were not done, they would feel the vengeance of his sword, and be subjected to punishment. The church always suffers when it has offenders in its bosom; it has the power of saving them if it will repent of its own unfaithfulness, and will strive for their conversion.

With the sword of my mouth. See Barnes on "Re 1:16; 2:12".

That is, he would give the order, and they would be cut as if by a sword. Precisely in what way it would be done he does not say; but it might be by persecution, or by heavy judgments. To see the force of this, we are to remember the power which Christ has to punish the wicked by a word of his mouth. By a word in the last day he will turn all the wicked into hell.

{a} "and will fight" Isa 11:4