Paul says he didn’t live by the standards of this world, but by another standard. It was a standard in which he didn’t fight matters the way the world fights matters.
By the humility and gentleness of Christ, I appeal to you—I, Paul, who am “timid” when face to face with you, but “bold” toward you when away! I beg you that when I come I may not have to be as bold as I expect to be toward some people who think that we live by the standards of this world. For though we live in the world, we do not wage war as the world does. The weapons we fight with are not the weapons of the world. On the contrary, they have divine power to demolish strongholds. We demolish arguments and every pretension that sets itself up against the knowledge of God, and we take captive every thought to make it obedient to Christ. And we will be ready to punish every act of disobedience, once your obedience is complete.
The world fights one way, but those in Christ fight differently. How? The text doesn’t specifically say in all matters, but we know from previous Scriptures the focus was on prayer and preaching.
Prayer is what gives divine power. And preaching/teaching/correcting is the means by which arguments are demolished and anything that sets itself up against the knowledge of God.
Paul makes note that this is not just what they preach, but what he himself also works to do – taking captive every thought to make it obedience. It’s not just what we argue about, it’s also about the truth and lies in our heads and hearts.
But Paul also makes no concession. If needed, he will confront disobedience. He says that he has the authority to do so, and it is not an authority to tear people down, but to build them up.
This is true. A loving parent will always bring discipline and correction not to destroy them, but to mold them into mature people. It is love and the building up but with the truth of hard things and sometimes, discipline.
What does that mean for us? It means we do not fight like the world, but we fight in prayer and in proclamation of the truth, even correcting error theologically and if someone is in a position of leadership, then bring correction and discipline in love.