What was the Corinthian church like when Paul wrote to them?

When Paul wrote, the Corinthian church was not huge but had a good cross-section of Corinthian society who had become believers. Paul says there was not a wise man among them. They were all believers, designated the wisdom of God, yet he spoke to their shame.

Les explains that the Corinthian church was not a huge congregation, but it drew a fairly broad cross-section of Corinthian society who had become believers. Paul nevertheless says there was not a wise man among them, even though they were all believers and had been designated the wisdom of God; he speaks this to their shame. The issue involved judgments about things pertaining to this life. Instead of depending on the most eminent or those with more worldly goods, Paul tells them to set the least esteemed in the church to judge, using the person at the bottom of the totem pole. He also reminds them that believers will judge angels and rule and reign with Christ, so they should be able to handle matters of this life.

1 Corinthians 6:5

I speak to your shame. Is it so, that there is not a wise man among you? no, not one that shall be able to judge between his brethren?

What was the makeup of the church in Corinth?

The church in Corinth was not a large congregation. It consisted of a good cross-section of the society of Corinth who had become believers. Paul addressed them as believers who had been designated the wisdom of God, though he rebuked them for lacking a wise man among them.