Purpose of Writing:
The church in Corinth began in AD 52 when Paul visited there on his second missionary journey. He stayed one and a half years, accomplishing much for the sake of the gospel. A record of this visit and the establishment of the church is found in Acts 18:1–18.
In his second letter to the Corinthians, Paul expresses his relief and joy that the Corinthians had received his “severe” letter (now lost) in a positive manner. That letter addressed issues that were tearing the church apart, primarily the arrival of self-styled (false) apostles (2 Corinthians 11:13) who were assaulting Paul’s character, sowing discord among the believers, and teaching false doctrine. They appear to have questioned his veracity (2 Corinthians 1:15–17), his speaking ability (2 Corinthians 10:10; 11:6), and his unwillingness to accept support from the church at Corinth (2 Corinthians 11:7–9; 12:13). There were also some people in Corinth who had not repented of their licentious behavior, another reason he had sent the “severe” letter (2 Corinthians 12:20–21).
Paul was overjoyed to learn from Titus that the majority of Corinthians had repented of their rebellion against Paul (2 Corinthians 2:12–13; 7:5–9). The apostle encourages them for this in an expression of his genuine love (2 Corinthians 7:3–16). Paul also urged the Corinthians to finish collecting an offering for the poor (chapters 8—9) and to take a harder stance against false teachers (chapters 10—13). Finally, Paul vindicated his apostleship, as some in the church had likely questioned his authority (2 Corinthians 13:3).
For a more detailed summary select the link below.
The Book of 2 Corinthians Summary