1 Corinthians 4:8 (ESV)

8 Already you have all you want! Already you have become rich! Without us you have become kings! And would that you did reign, so that we might share the rule with you!

Moreover, the Corinthians imagine themselves to possess things that, in truth, they do not possess. They imagine themselves to be kings. The end of the verse shows that Paul’s portrayal of the Corinthians as kings is merely ironic. The truth is that neither the Corinthians nor the apostles have been given the authority to reign in this world.

Paul’s frequent references to God’s kingdom in the rest of the letter (1 Corinthians 4:20; 1 Corinthians 6:9–10; 1 Corinthians 15:24, 1 Corinthians 15:50) suggest that the Corinthians may have had a faulty understanding of the kingdom. This caused them to rule in an inappropriate, worldly way. Paul may be thinking of their extravagant feasts (1 Corinthians 11:17–22), their hasty judgments of others (1 Corinthians 4:5), and/or their fascination with worldly wisdom (1 Corinthians 3:18–21).

God does promise that believers will be rulers in his kingdom. However, this is a promise for the future, when Christ returns (2 Timothy 2:12; Revelation 5:10; Revelation 22:5).