What was the spiritual condition of the Corinthian church that Paul was writing to?

The Corinthian church was spiritually immature—babes in Christ and carnal. Though the gospel had taken hold enough to bring them out of paganism and they had separated from their pagan background to a degree, they remained carnal and had a long way to go in spiritual growth.

Les teaches that Paul did not lose sight of the spiritual level of the Corinthian church. They were babes in Christ and carnal, not Paul’s pride and joy of spiritual growth like the Ephesians or Philippians. Even so, Paul loved these carnal believers, saying his mouth was open to them and his heart was enlarged toward them. They were not straitened in him, but straitened in their own bowels—meaning their innermost being or heart. Les explains that the gospel had taken hold of the Corinthians enough to bring them out of paganism, and they had separated themselves from their pagan background to a degree, but they were still carnal and had a long ways to go.

2 Corinthians 6:11

O ye Corinthians, our mouth is open unto you, our heart is enlarged.

What did Paul mean in 2 Corinthians 6:11 when he said his heart was enlarged toward the Corinthians?

Paul meant his heart was enlarged toward the Corinthians as an open pouring out of his innermost being. He was not restricting them; rather, they were straitened in their own innermost being. He urged them to be enlarged too, that is, to have the same kind of spiritual relationship with him.