Corinth had a problem with false teachers. Paul wrote this letter to defend his ministry and title as an apostle. He spends time validating his message to the people. He also talks about looking out for others who are less fortunate and finding strength in God.
2 Corinthians 12:9-10 -- “Each time he said, “My grace is all you need. My power works best in weakness.” So now I am glad to boast about my weakness, and in the insults, hardships, persecutions and troubles that I suffer for Christ. For when I am weak, then I am strong.”