10:4 for the weapon are not of the flesh,
but mighty before God to the throwing down of strongholds,
10:5 throwing down imaginations and every high thing
that is exalted against the knowledge of God,
and bringing every thought into captivity to the obedience of Christ;
10:6 and being in readiness to avenge all disobedience,
when your obedience will be made full.

10:8 For though I should boast somewhat abundantly concerning our authority,
(which the Lord gave for building you up, and not for casting you down)
I will not be disappointed,

10:17 But "he who boasts, let him boast in the Lord."(Jer 9:23,24)
10:18 For it isn't he who commends himself who is approved,
but whom the Lord commends.

vs 2 In the rest of the book of 2nd Corinthians, Paul deals with Christians who question his authority. The particular standards of the world he is referring to is the tendency of worldly authorities to lord over those under them rather than to have a servant attitude looking towards their edification. They inferred that since Paul gave alot of commands and was from their point of view rather harsh in 1st Corinthians, therefore he was behaving as a mere human authority. And indeed I have met those today who treat his commands in 1st Corinthians as merely his own human opinion.

vs 3-5 The world exercises its authority by the sword. This was particularly well illustrated by the often violent oppression of the Roman Empire. But also religious movements have also been ruled by violence. Even during the Protestant Reformation, the false doctrine of infant baptism was propagated with the threat of violence if one taught contrary to it, for example. And other religions, like Islam, have propagated and been sustained through violence and the threat of violence, as also did Catholicism in the dark ages.

But Biblical Christianity doesn't operate that way, as Jesus himself revealed by his lifestyle. Yes he did preach of the judgement of hell, but he wasn't a violent man, nor did he promote his ideas through violent acts as the world does. On the other hand, Christians should not view themselves as pacifists in propagating the gospel and living the Christian life. For it is described as spiritual warfare. I find "Feel-good" Christianity which has found a foot hold in many churches today, doesn't allow a critical evaluation of itself. Nothing critical which makes people feel bad is allowed in such churches. People must gullibly accept whatever dogma such institutional leaders preach and spiritual warfare against the leaven of such teachings and practices is reckoned itself to be sinful as it promotes divisiveness from their point of view. Such is the attitude of Paul's enemies in the Corinthian church.

We must learn to take every idea captive to the obedience of Christ. Evaluate your own ideas and those of others and compare them with the Biblical truth. That's what Paul was doing. And what did he do if he found false ideas? He demolished them. Jesus did the same, as you read of his interaction with the Pharisees and others who had false ideas. Yet many institutional leaders would like you to accept their ideas  and lectures as the Word of God without question. Are you allowed to question the ideas of your pastor? Does he even allowed feedback on what he says? Even Paul considers skepticism virtuous as it is written:

"Now the Bereans were of more noble character than the Thessalonians, for they received the message with great eagerness and examined the Scriptures every day to see if what Paul said was true." Acts 17:11 (niv)

"Do not believe me unless I do what my Father does. But if I do it, even though you do not believe me, believe the miracles, that you may know and understand that the Father is in me, and I in the Father." John 10:37,38 (niv)

Paul's practice of spiritual warfare is revealed in his letters. It is not simply a fight against his own sinfulness, nor is it simply evangelism directed at the world. For his main field of battle is the church life. Going to church is like going to war - battling  false ideas and sin in the church, building up the believers preparing them for war and converting the nominal Christians to true faith in Christ.  Such activities are supressed in most modern churches, where ecumenical pluralism and making people feel good about themselves is the order of the day in such social clubs. Indeed most Christians are not allowed to speak at all at church, other than sing songs, but simply listen to a lecture and go home.

vs 6 "When your obedience is complete". By "obedience" he is referring to complying to his commands. "is complete" is in the subjunctive - the mood of possibility, but not certainty - communicating his doubt and criticism as to whether they'll ever get to that point, as he wrote previously "Brothers, I could not address you as spiritual but as worldly-- mere infants in Christ." Corinthians 3:1 You don't deal with children in the same manner as with those who are mature. You have higher expectations and demands of those who are supposedly mature, as the more mature we are the more responsible we should be and thus will be held more accountable. (Maybe that explains why many would like to stay immature in their faith and practice).

vs 7 "Looking only on the surface" is an indication of immaturity. As they say, "You can't judge a book by its cover." The gullible look only on the surface. And many Christians are only Christians on the surface. And many have shallow Christian relationships. Compare your relationship with other Christians with Paul's deep relationships with the believers of his time. But in particular Paul is speaking of "looking" only on the surface. We should be looking deeper into the implications of ideas. We should be looking deeper into people and their motivations. Paul encourages and even explicitly commands examination as to whether we or others are truly in Christ.

"Examine yourselves to see whether you are in the faith; test yourselves. Do you not realize that Christ Jesus is in you-- unless, of course, you fail the test?  And I trust that you will discover that we have not failed the test." 2Cor 13:5

vs 8 Paul had one weapon that none of his opponents could claim. He had been officially appointed by Jesus Christ to be an apostle. He reminds them again that this is for their edification. Of course today many "feel-good" types would say that because he made people feel bad, as he admits in 2Cor 7:8-11, he was therefore pulling them down. But as he explained in that section, such was for their edification like a father disciplining his children.

vs 9-11 This is what vs 1 was eluding to - that people were making such claims of hypocrisy. I suspect what was happening is sort of "when the cat is away, the mice will play."  When Paul was with them, people didn't tend to misbehave, just as children when their parents are around. And thus he didn't have to deal with them harshly. But when he left, they started to misbehave, and so he had to discipline them by letter. But if they misbehaved in his presence, he's saying that he would discipline them too.

vs 12 Elitism can be quite common in institutional Christianity. Doctrine centers around human dogmatism rather than the authoritative Word of God. People will put their own words above the apostles. But John writes:

"We are from God, and whoever knows God listens to us; but whoever is not from God does not listen to us. This is how we recognize the Spirit of truth and the spirit of falsehood." 1John 4:6

vs 13-18 A common attitude among elitists is to take credit for other people's work. Taking false credit is what got Ananias and Sapphira killed in Acts 5. There are those who boast that they go to a large church with a great pastor like Apollos and where people have alot of spiritual gifts. But they themselves may be doing nothing, but just be observers and perhaps even merely nominal Christians. And there are even ministers who take credit for the work of members of their congregation, yet contribute little to their efforts.

Paul limited his boasting to his realm of responsibility and to his actual activities. Never mind what your church is doing, what are you doing for Christ that you can boast about? And what should you be doing for Christ? What is your realm of authority? While he was on earth, even Jesus limited his realm of activities to Israel and to discipling the twelve. But once the Corinthians mature, just as with parents being freed up once the children leave the nest, so Paul would be able to expand his ministry, concentrating on others who are in need of maturity. For we shouldn't just stick around the mature, like a pillar of salt. For it is not the healthy that need a doctor but the sick.