Charles Ellicott Commentary Revelation 13:10

"If any man [is] for captivity, into captivity he goeth: if any man shall kill with the sword, with the sword must he be killed. Here is the patience and the faith of the saints." — Revelation 13:10 (ASV)

This verse may read: If anyone (is) for captivity, into captivity he goes; if anyone is to be killed by the sword, he should be killed by the sword. If we read the verse thus, it is generally understood to be a caution to the suffering saints that there is nothing for them but to endure, just as Jeremiah told his countrymen that those who were for death must go out to meet it, and those who were for sword or captivity must face them (Jeremiah 15:2).

But is not this a warning to them that the way of the Church’s victory lay through suffering captivity and meeting sword, and that the temptation to take the sword or seize the weapons of their foes would be fatal to their true success? The spirit of the words reminds them that their weapons are the weapons of faith and patience, of truth and righteousness; and they must accept the tribulation, as their Lord did His cross, because thus it must be.

At the same time, their very doing so is a witness to their foes that all those who take the sword will perish with the sword; and that the sword, from which the saints do not shrink, will assuredly turn against those who use it. Here (i.e., in the enduring of these persecutions, and amid so many temptations, not seizing easy, world-like methods of saving themselves) is the endurance and faith of the saints.