Jesus answered, “My kingdom is not of this world. If My kingdom were of this world, My servants would fight, so that I should not be delivered to the Jews; but now My kingdom is not from here.”
– John 18:36 (NKJV)
My kingdom is not of this world. By these words he acknowledges that he is a king, but, so far as was necessary to prove his innocence, he clears himself of the calumny; for he declares, that there is no disagreement between his kingdom and political government or order; as if he had said, “I am falsely accused, as if I had attempted to produce a disturbance, or to make a revolution in public affairs. I have preached about the kingdom of God; but that is spiritual, and, therefore, you have no right to suspect me of aspiring to kingly power.” This defense was made by Christ before Pilate, but the same doctrine is useful to believers to the end of the world; for if the kingdom of Christ were earthly, it would be frail and changeable, because “the fashion of this world passeth away” (1 Corinthians 7:31); but now, since it is pronounced to be heavenly, this assures us of its perpetuity. Thus, should it happen, that the whole world were overturned, provided that our consciences are always directed to the kingdom of Christ, they will, nevertheless, remain firm, not only amidst shakings and convulsions, but even amidst dreadful ruin and destruction. If we are cruelly treated by wicked men, still our salvation is secured by the kingdom of Christ, which is not subject to the caprice of men. In short, though there are innumerable storms by which the world is continually agitated, the kingdom of Christ, in which we ought to seek tranquility, is separated from the world.
We are taught, also, what is the nature of this kingdom; for if it made us happy according to the flesh, and brought us riches, luxuries, and all that is desirable for the use of the present life, it would smell of the earth and of the world; but now, though our condition be apparently wretched, still our true happiness remains unimpaired. We learn from it, also, who they are that belong to this kingdom; those who, having been renewed by the Spirit of God, contemplate the heavenly life in holiness and righteousness. Yet it deserves our attention, likewise, that it is not said, that the kingdom of Christ is not in this world; for we know that it has its seat in our hearts, as also Christ says elsewhere, “The kingdom of God is within you” (Luke 17:21). But, strictly speaking, the kingdom of God, while it dwells in us, is a stranger to the world, because its condition is totally different.
My servants would strive. He proves that he did not aim at an earthly kingdom, because no one moves, no one takes arms in his support; for if a private individual lay claim to royal authority, he must gain power by means of seditious men. Nothing of this kind is seen in Christ; and, therefore, it follows that he is not an earthly king.
But here a question arises, Is it not lawful to defend the kingdom of Christ by arms? For when Kings and Princes are commanded to kiss the Son of God (Psalm 2:10-12), not only are they enjoined to submit to his authority in their private capacity, but also to employ all the power that they possess, in defending the Church and maintaining godliness. I answer, first, they who draw this conclusion, that the doctrine of the Gospel and the pure worship of God ought not to be defended by arms, are unskillful and ignorant reasoners; for Christ argues only from the facts of the case in hand, how frivolous were the calumnies which the Jews had brought against him. Secondly, though godly kings defend the kingdom of Christ by the sword, still it is done in a different manner from that in which worldly kingdoms are wont to be defended; for the kingdom of Christ, being spiritual, must be founded on the doctrine and power of the Spirit. In the same manner, too, its edification is promoted; for neither the laws and edicts of men, nor the punishments inflicted by them, enter into the consciences. Yet this does not hinder princes from accidentally defending the kingdom of Christ; partly, by appointing external discipline, and partly, by lending their protection to the Church against wicked men. It results, however, from the depravity of the world, that the kingdom of Christ is strengthened more by the blood of the martyrs than by the aid of arms.