This book isn’t that long, but it is potentially difficult to understand unless you go slow because there is so much packed in here. The reason why Paul writes is that some outsiders have come to the churches in Galatia and told them that in order to be good Christians they have to also be good Jews. That means they have to keep the Law, including being circumcised, eating kosher food, and keeping the Sabbath. This is nonsense, Paul says! It’s not just dumb, it’s dangerous!
Salvation comes free by believing in what Jesus did for us. By trying to do other things (like circumcision), you are saying that what Jesus did was not enough and you have to make up for it. This makes Paul very, very mad. He tells his readers that if they follow the Law, they will not be following Jesus and they will go to hell.
For details on what this “Bible Reading Guide” series is about, see the first post.
Some years ago, I wrote Galatians on one foot.