What does 2 Corinthians 11:19 mean?

Paul has written that he is about to do something foolish. Like his opponents in Corinth, he too will boast "according to the flesh" or in order to bring glory to himself. He's very clear that this is being done—almost with sarcasm—to prove a point. He has described worldly bragging as something fools do, not something the Lord would expect. To further prove his point, Paul's "boasting" will mostly focus on God's power through him in his weakness and not about any achievements of his own.

The Corinthians should tolerate his boasting—they have gladly put up with fools teaching falsehoods about Jesus! The Corinthians do so, Paul adds, because they are so wise. He is being satirical, as he was when he wrote about their great wisdom in 1 Corinthians 4:10. There he said sarcastically that he and his associates were "fools for Christ's sake, but you are wise in Christ."

It is possible the Corinthians thought themselves wise enough to admire Paul's impressive-sounding opponents and decide for themselves what was true and what was not. Paul wryly says they should be willing to hear his foolishness out, as well.