What does 2 Corinthians 4:7 mean?

What is the treasure Paul describes in this verse? From the previous verse, we know that it is the "light of the knowledge of the glory of God in the face of Jesus Christ" (2 Corinthians 4:6). Paul described God as shining His light into Paul's heart, penetrating the darkness of Paul's unbelief and revealing His glory to Paul through faith in Christ. Paul finally saw with spiritual eyes what he had never seen in all of his years of religious practice. In fact, Paul's phrasing in the prior verse incorporates the values of many different cultures—light, knowledge, and glory—and expresses them in the form of a person which is Jesus Christ.

To know God in this way, to see God's glory and to be given the opportunity to share in that glory forever, is the greatest of all treasures. Paul writes now that this great treasure is not kept under lock and key in a museum or a bank vault. Instead, God keeps this treasure of the light of His glory in Christ in fragile jars of clay. Clay jars were included in nearly every aspect of life in Paul's day. They were efficient containers, but also prone to breaking easily. Modern people tend to think of glass jars as "fragile," but glass was considered an improvement over clay.

The point being made is that God has deliberately chosen something fragile and unimpressive. Why would God keep this great treasure in such vulnerable containers? Paul says God wants to show that the power of His glory is from Him. He leaves no room to suggest that power comes from Paul or any other human being. The power of the gospel is so overwhelming that it is not limited by the quality of its container. God displays His limitless power and glory by distributing it through limited and common human vessels.

This follows Paul's point in verse 5 that he has not come to proclaim himself as something special. He has come to proclaim Christ as Lord, with himself merely a servant to the Corinthians for Christ's sake.