Why should the Corinthians have commended Paul according to 2 Corinthians 12:11?
The Corinthians should have commended Paul because he brought them out of paganism and into the light of the gospel of God's grace, and because in nothing was he behind the very chiefest apostles. Instead, they accused him, forced him to boast, and failed to give him rightful credit.
Les explains that the Corinthians had compelled Paul to glory or boast by constantly accusing him of not being a rightful apostle. They said he had no authority and no letters of commendation. Unlike Peter, he could not claim three years with Christ. Yet Paul says he ought to have been commended by them because he was the one who brought them out of paganism and into the light of the gospel of the grace of God. They were now turning against him and not giving him credit. He repeats that in nothing was he behind the chiefest apostles, though he was nothing; he did not claim to be anybody, but as God's instrument he was everything. The Holy Spirit repeats needed truths.