What does 2 Corinthians 3:9 mean?

Paul is contrasting two covenants God has had with His people. The first is the Old Testament, the initial agreement God had with the nation of Israel. If they would follow His law, He would give them abundant life. If they disobeyed, he would bring judgment.

Paul has described that covenant as the "ministry of death," because those who tried to follow God's law learned they could not. They understood their sinfulness deserved death, often covered by the death of animals in sacrifice. Paul now describes it as the "ministry of condemnation."

The new covenant is different. God offers forgiveness of sin to all who come to Him through faith in Jesus. By His grace, He gives credit for Christ's righteous life and takes Christ's death on the cross as payment for sin. He places His Holy Spirit in all who trust in Christ in this way, guaranteeing an eternal place with Him in glory.

Paul now describes this as the "ministry for righteousness," because God declares believers to be righteous in Christ. No condemnation remains for them (Romans 8:1).

Since all those in Christ will share in God's glory for eternity, it's no wonder that Paul declares here that the ministry of righteousness will far exceed the ministry of condemnation in glory.