In the first half of this chapter, Paul scolded the Galatians

You know how sometimes, as a parent,
- when you're very worried about your child–maybe they did not arrive home on time
• when they finally show up, your worry turns to anger
◦ if ever our lectures were rougher than they needed to be,
◦ it was because we had agonized over their safety
• I think that's a little piece of what is happening here
◦ Paul has called the Galatians "foolish" and asked "Who has bewitched you?"
◦ that is because they had him worried about the stability of their faith
- it is often the people who are most concerned with pleasing God,
• that are misled by false preachers and teachers
◦ they desire so much to be absolutely right with God that they fall victim to someone who seems knowledgeable
• anyway, Paul' agitation rises to the surface in these short, clipped statements that barely say enough
- here in verse 15, he presents Abraham as an example of being true to a promise