PPARENTLY, the Corinthian believers were somewhat critical of Paul and his ministry (vs. 3). Never mind that he was their spiritual mentor. They acted like spiritual teenagers: a little defiant and a lot too big for their own britches. In fact, if you read between the lines, you will notice that Paul turns the Corinthians' own critical gun against them. They were questioning Paul's position and the rightfulness of his authority. He accepted this up to a point, but then he challenged them to use the same attitude of caution and zealous differentiation while looking in the mirror (vs. 5). It seems that they had expressed concern over whether perhaps Paul and his companions in ministry were reprobates, or true teachers. So Paul asked if perhaps there were reprobates in Corinth. He was literally allowing for the possibility that some of those who claimed to be his converts were still lost and on their way to hell.
One thing is sure, the next time he made it to Corinth, Paul intended to preach a rather stinging hellfire and brimstone message in order to purge the church of what he perceived to be an unclean spiritual element. Paul did not relish such an occasion, but he was willing to exercise his apostolic responsibility in order to promote spiritual perfection in this church.
As already stated, Paul loved the Corinthians dearly. In closing this letter, his farewell remarks gently express his loyalty to true doctrine & to the persons of the Godhead. Yet shining through is Paul's sincere desire for wholeness & holiness among his friends (vs. 10-14). He offered a simple yet perfect balance of orthodoxy & compassion. Paul expected & demanded that truth be accepted continually yet he was noticeably patient with his friends in the faith.