What does 1 Corinthians 3:20 mean?
One cannot hold on to human wisdom and God's wisdom at the same time, or in equal measure. They are opposed to each other. Human wisdom can only go so far, and soon reaches its limits (Isaiah 55:8–9). Once that limit is reached, reliance only on our own wisdom leads to rejecting faith in Christ and His death on the cross for sin. Without the revelation of God's truth through God's Spirit, a fallible human being simply cannot comprehend it (1 Corinthians 2:14). So, the non-believer considers it foolish (1 Corinthians 1:18).Because of this, every man-centered thought of those wise in human terms is wasted (Colossians 2:8). Ungodly assumptions are based on the wrong premises since they have eliminated God's wisdom and faith in Christ as a possibility.
Paul quotes from Psalm 94:11 to sum it up. The Lord knows the thoughts of those wise in human wisdom are ultimately futile (Romans 1:18–23). All their thinking leads away from the truth instead of nearer to it. Without receiving the revelation of the spiritual truths of God with the help of the Holy Spirit, human wisdom remains worthless in the long run.