5 Examine yourselves as to whether you are in the faith. Test yourselves. Do you not know yourselves, that Jesus Christ is in you?—unless indeed you are disqualified. 6 But I trust that you will know that we are not disqualified.
The Corinthians put Paul to the test about the genuineness of his apostleship. Now he turns the table on them; he puts them to the test.
5 Examine [test] yourselves [emphatic]
No believer ever moves beyond the need for self-evaluation (1 Co 11:28; Ga 6:4). Some in Corinth needed to conduct a personal audit of their standing with God. The Corinthians blissfully critiqued Paul’s ministry without examining themselves. God requires genuine Christians to evaluate where they were spiritually.
as to whether you are in the faith [the Christian faith, the objective doctrinal faith].
The idea here is to see whether the Corinthians held to an unshakable faith, the Christian view of salvation. They needed to stand firm in the faith (2 Co 1:24). Paul does not deny that they are Christians; otherwise, he would not have expected them to administer the test. The test for them was whether they lived their lives like Christ and Paul, lives of weakness which looked to God’s power.
Test [prove] yourselves [emphatic].
The Corinthians should examine themselves, not the apostle. The Greek word for “test” means to put something to the test to determine whether it is genuine. There is a danger in self-deception. That is why a spiritual audit is necessary at times.
Do you not know yourselves, that Jesus Christ is in you? Yes
The Greek expects a “yes” answer to the question. The Corinthians could not test or prove themselves unless their faith was genuine. Their verdict about themselves is the same verdict about Christ. If the Corinthians doubted the genuineness of Paul’s apostleship, then they would have questioned the basis for which they became Christians; thus, they would have to doubt their salvation.
—unless indeed you are disqualified [unproven, disapproved by trial].
Paul earlier asked the Corinthians to determine whether they are approved in 2 Corinthians 2:9.
6 But I trust that you will know [fully] that we are not disqualified [disapproved].
The Corinthians will see by testing themselves that Paul is not disqualified for ministry. If people in the church examine themselves, then they will realize that the person who led them to Christ is authentic. Paul would pass the test of their own making. The proof they seek in Paul, they will find in their salvation. If the Corinthians can detect salvation in themselves, they should see the authority of the apostle Paul.
If we are not honest with ourselves, we cannot mature in Christ.
Self-examination is the way we determine how mature we have become. Maturity is the application of the principles of Scripture to experience by faith. By faith, we apply a passage of Scripture that pertains to our sin, our vulnerabilities. As we keep applying God’s Word to experience, we progressively mature in Christ. See this study: https://versebyversecommentary.com/articles/christian-maturity/the-edification-construct-discussion-guide/
Christians cannot bypass Christ’s pattern of weakness, which is foolish to the world system. God’s power can be seen in what He does, not what we do (1 Co 4:10; 2 Co 4:11). Our weakness should reflect itself in what God does through us, not what we do. This is the paradox of Christian dynamics. God’s power does the work (1 Co 3:12-15).
People occupied with their self-importance in ministry are dangerous to the cause of Christ. They are examples of those who deny the grace of God required for godly living. Christian behavior is the touchstone to determine whether our claims about Christianity is valid.