“He is not weak in dealing with you, but is powerful among you” (v3). Paul said that he would bring Christ’s spiritual power to confront the Corinthians in the church who persisted in sin (v1-2). Their behavior endangered themselves and others. Paul urged them to “examine themselves, to see whether you are in the faith” (v5). The point of this “test” (v5) was to see evidence of the living Christ in their hearts and lives – and if not, to repent. Christ’s power was available for correction and restoration.
“I warned those who sinned before …” (v2). Sin is nothing to take lightly, especially among those called by Jesus’ name. God calls us to holiness and wholeness.