What did Israel do with all the advantages God gave them?
Israel had much going for them in the Old Testament, yet they failed miserably over and over. They did not rightly use what they had. Their repeated failure is contrasted with the Corinthians, who did the same despite strong teaching and preaching.
Les explains that Israel, in the Old Testament, had much going for them, yet they failed miserably over and over. He compares this to the Corinthians, who also had many advantages: the apostle himself as their spiritual father, Timothy as his spiritual son who would remind them of Paul's ways in Christ, and the strong teaching and preaching of the greatest apostle. Despite all this, the Corinthians were doing the same thing as Israel—failing.
Now some are puffed up, as though I would not come to you.