The sermon is about the Samaritan named Simon. There are three points.
1) Gospel Transformation: the city of Samaria is transformed by the gospel as Philip preaches it. They go from believing all sorts of error to believing the truth about the Messiah. They go from listening to and following Simon to listening to and following Jesus as the great power and Savior.
2) Spirit Authentication: the boundary crossed from Jew to Samaritan was significant and because of this the Spirit didn’t come on them right away. Instead, there was a delay- so the apostles could come down, be a part of and witness the full inclusion of the Samaritans as demonstrated in their full reception of the Spirit. They are now to be fully welcomed into the New Covenant community.
3) Wicked Distortion: Simon- who professed faith- ends up to be a counterfeit- all he wants is the power- and he wants to buy it like its a product that he can use to become powerful and prominent again. There are scary tendencies here: 1) to think we can somehow earn or purchase salvation or the gifts that come with it 2) to think of Jesus as a product that we use for what we want. Instead, we’re called to bring our nothing, submit to Jesus as King, see him as our great treasure, and trust in his purposes for us.