What was the Book of Galatians written to correct?
The Book of Galatians was written to correct the Galatians' legalism. They were slipping off course, and the letter was literally sent to bring them back on course. Its purpose was correction, pulling them away from legalistic error and restoring them to the right path.
Les explains that Galatians was written for correction, which fits the fourth position in the Church-letter order: Romans for doctrine, Corinthians for reproof, and Galatians for correction. The Galatians were slipping off into legalism, so the Book was literally written to bring them back on course. Even though Galatians was written earlier than Romans, the Holy Spirit placed it in the New Testament order where it belongs.