Why did St. Paul write the letter to Galatians?

Paul wrote his letter to the Galatians primarily to address a false teaching that had infiltrated the Galatian church and was undermining their faith. This false teaching emphasized the necessity of following Jewish law and practices for salvation, even after receiving faith in Christ. Paul was deeply concerned about these deviations from the true gospel.

Key reasons for writing his letter to the Galatians include:

1. Rectifying doctrinal errors: The false teaching was leading the Galatians astray, endangering their salvation, and potentially disrupting unity within the church. Paul sought to correct these doctrinal errors and reaffirm the simplicity of salvation by faith in Christ alone.

2. Defending his apostleship: Some Jewish Christian teachers criticized Paul's apostleship because he didn't require Gentile Christians to obey Jewish Law. By recounting his encounter with the apostles during his apostleship and asserting his direct call from Christ, Paul affirmed his authority and defended his gospel message.

3. Reinforcing the freedom in Christ: Paul emphasized that Christians are no longer under the slavery of the Law through Christ's redemptive work. Through faith and by God's Spirit, believers find inner liberation and peace.

4. Promoting unity: Paul passionately pleads for unity among Jewish and Gentile believers (Galatians 3:27-28) and rebukes the dividing tendencies that threaten church harmony.