What does Galatians 1:6 mean?

Paul began his letter with a brief, beautiful explanation of what the gospel message—the "good news"—about Jesus truly is. Jesus gave His life to pay for human sin before being returned to life by God the Father. Scholars call this "substitutionary atonement," meaning Jesus took our place and paid the full penalty for our sin. Without that, we would be trapped and doomed to death instead of delivered from "this present evil age" (Galatians 1:4).

Now Paul turns fully to the reason for this letter. He speaks directly to people who believed the gospel of Jesus when Paul told them about it on his first missionary journey to their region. They heard the simple truth that through faith in Christ, they could be saved from their sin. No extra works were required to assure their place in God's family. Jesus had paid in full with His life.

As will become clear, Paul is frustrated with his readers, if not angry. He is, in fact, "astonished" that they are so quickly turning away from the simple truth. More specifically, Paul writes that they are deserting or abandoning Christ Himself by believing a different idea, a different "gospel," than the one he showed them.

What's going on? As the following verses will make clear, a group of religious people had moved in among the Galatian Christians after Paul left, distorting what Paul had taught. They said, in short, specific works or actions were necessary to truly be saved. Simple faith in Christ alone was not enough. Paul writes here that to reject his faith-alone gospel was to reject Christ Himself.