Paul's ministry among the Corinthians is probably one of the best examples in Scripture to learn about people, especially people in the church. Actually the Apostle Paul was very charitable to the parishioners at Corinth. His charitable spirit was not without a stern warning to the Corinthians. Paul says, "do you not know that the unrighteous shall not inherit the kingdom of God?" Then he goes on to enumerate certain character traits that will preclude one from inheriting one square inch of the New Heavens and New Earth. Although Christians must not dwell on that aspect of the Gospel, there is much to learn from the Apostle Paul as he writes to the Corinthians.
It is apparent that factions in the church were a problem, just as they are today. Paul alludes to the problem in several places, but makes a significant statement that I have personally wrestled with for some time. Paul says, "be made complete in the same mind” and I wonder what he means by that statement. Later on in his ministry he said to the Philippians "I have no one else of kindred spirit" referring to Timothy. Is Paul saying that out of all his disciples that Timothy is the only one who is like-minded with Paul? Does he really mean that the Corinthians be like-minded or is that just a standard he has set for them? Maybe the Apostle said that to warn of the denominations already present in the Corinth Church.
The Christians at Corinth may not have been very bright or they may not have been properly instructed in the Word of God. Paul spoke to them as "babes in Christ." Paul modifies that a bit indicating that he had only fed them milk 1 Cor. 3:1,2). Christian teachers must use skill and prudence in feeding doctrinal truth to babes in Christ. However, by the sanctifying power of the Holy Spirit there ought to be spiritual growth in the treasures found in the word of God.
The church at Corinth had discipline problems. They were liable to the judgment of God and Paul makes that very clear. He said, "Remove the wicked man from among yourselves." God's judgment is certain and universal, but for the local church it is limited and partial. Some people in the Corinthian Church were sinful and needed to be removed from the fellowship.
The church members at Corinth had some pretty serious hang-ups, but apparently Paul does not give up on their hang-ups. He exhorts them for sure, but he gives them assurance that they are not the only ones who have problems. "No temptation has overtaken you but such as is common to man. . ., so says Paul the Apostle. Gossip, dissension, sexual hang-ups, lack of desire to grow up in Christ, etc. are the same problems that have bugged man since the fall. What is the answer? Paul says "I show you a still more excellent way" but even the excellent way is often dim to struggling Christians.
Christians ought to pray that God will help them minister to the Corinthians wherever they minister in the name of the Lord Jesus Christ.