1 Corinthians 3:18 (ESV)

18 Let no one deceive himself. If anyone among you thinks that he is wise in this age, let him become a fool that he may become wise.

Earlier (in 1 Corinthians 2:6–16), Paul had described the wisdom that comes from the Spirit. Then (in 1 Corinthians 3:1–17) he focused on problems inside the Corinthian church. Now (in 1 Corinthians 3:18–23) he finally shows the connection between these two themes. He directly warns the Corinthian believers not to cling to worldly wisdom. The wisdom of the world is what stimulates pride and partisanship.