2 Corinthians 10:4

For the weapons of our warfare are not carnal. Carnal weapons are such as serve for carnal and bodily warfare and life, as the honours, pleasures, and power of this world. This the Apostles did not use in their task of subduing the world to Christ. Or rather, as said above, carnal weapons are human arts, sciences, reasonings, systems, eloquence, flatteries, boasting, hypocrisies, affected gravity and prudence, all of which are used by men of the world to gain influence and respect; while true and solid authority, such as Paul and the other Apostles had, is the gift of God, and is not to be obtained by external gifts or by assumed gravity, but rather by the display of virtue, wisdom, and holiness.

But mighty through God. Or, are the power of God. Through them God works powerfully in the minds of the hearers converts them to the faith, makes them accept our preaching, brings them under subjection to Christ, so that we gain credence to what we say, and obtain what we want. These weapons are, says Anselm, (1.) Vehement spiritual zeal; (2.) Efficacious preaching, through God seeming to lend weight and force to our words; (3.) Wisdom; (4.) Courtesy; (S.) Holiness; (6.) Miracles; (7.) Frequent prayer; (8.) Purity of intention; (9.) Patience; (10.) Charity. When they see us men of the most blameless life, seeking not their wealth or honours, but their salvation only, and that by many labours, sacrifices, afflictions, daily death and martyrdom, and preaching to them with such zeal and ardour that all acknowledge Christ, and glorify Him and His Father by all these things, as though by a most powerful dart, they are struck and wounded in their consciences, they yield, and believe our words and our doctrines. By these weapons do we Apostles destroy the vices and storm the kingdom of the devil, even the whole world. Hence apostleship and preaching of the Gospel are rightly called a warfare. Cf. 1 Timothy 1:18.

To the pulling down of strong holds. All reasonings, syllogisms, sophisms, eloquence, philosophic virtues, worldly power, grace, friendship, and all that the Gentiles and devils opposed to the preaching of the Gospel by the Apostles (Chrysostom and Anselm). Ver. 5. Casting down imaginations. Or, with Theophylact reasonings. The Syriac and Erasmus give imaginations; the Latin version, counsels. By our weapons we destroy all the counsels of the prudent of this world, by which they strive to overthrow the Gospel, to strengthen against it their heathenism, and to put their philosophers before Christ and us.

And every high thing. Every height, both of human and philosophic wisdom, as well as of diabolic magic, such as of Simon Magus and others, and of royal and imperial power. Imaginations and heights were the two towers set up by the Gentiles against the Apostles, one of which seemed impregnable through its intricate wiles, and the other by its height and strength. Yet both yielded to the weapons of the Apostles.

That exalteth itself against the knowledge of God. That knowledge of God given to us by Christ, and which we, His Apostles, teach throughout the world; faith, that is, in the Three in One, in the Son of God, in His Incarnation and death, in the Cross and its Redemption.

And bringing into captivity. Every thought, every intellect, however full of resources, however exalted in wisdom, must surrender as a conquered foe, and obey the Gospel of Christ.

When S. Paul says "every thought" or "every intellect" he does not mean to imply that all the philosophers and mighty men of the world who heard the Gospel preached were converted, but that the weapons of the Apostles were so powerful that they were able to subdue to the faith of Christ any thoughts and reasonings of the human intellect, however full of wiles, however highly exalted. As a matter of fact, they did subdue these powers in those who took these weapons, and admitted them into their soul, and so were converted. Many of all classes of philosophers and orators, illustrious for their learning and wisdom, were subdued by the weapons of the Apostles, and brought to believe in Christ. Such were Dionysius the Areopagite, Clement of Rome, Paul the proconsul, Justin the philosopher, Athenagoras, and others. Ver. 6. And having in a readiness to revenge all disobedience. Paul had said that his weapons were powerful to subdue any Gentiles or heathen wise men. He now goes on to say that this same power is able to punish all disobedience on the part of the faithful, or amongst heretics. I am ready, he says, and it is easy for me, to punish the disobedience of the false Apostles who depreciate me, by excommunicating them.

When your obedience is fulfilled. For I am unwilling to involve you in the same punishment. I would rather that you yourselves correct what needs correction and I am waiting until you fulfil what you have been ordered. Then when you have done that, I will unsheathe the sword of excommunication against those contumacious detractors. From this doctors lay down that this sword should not be drawn except against the disobedient, and those who, after having been warned, are still rebellious and obstinate. Ver. 7. Do ye look on things after the outward appearance? The Latin version takes this in the indicative. Ye see how openly and manifestly the truth has been set before your eyes, that I am not only a disciple of Christ, but also an Apostle endowed with such spiritual power as you see with your own eyes (Anselm). Ver. 8. Of our authority, which the Lord hath given us for edification. The Council of Trent (sess. xxv. c. 3) lays down from these words that the sword of excommunication should be soberly and cautiously drawn for edification; otherwise we see that it is rather despised than dreaded, and produces ruin rather than salvation, not only to the excommunicated, but also to the whole Church.