It’s funny how perspective changes when you read through an entire Gospel, versus discussing individual stories from the same book. When you take a story by itself, it’s usually pretty easy to get the surface-level meaning and application. In context, with this one in particular, I wonder, “Why is this here, in this chapter? What else do we learn from the next and previous passages together with it?”
That said, I don’t think I have any answers to those questions. As best I can tell, Luke is reminding us that Jesus is on His way to Jerusalem for the last time, and this is something that happened on the way. Ten lepers met Jesus, apparently knew who He was, and asked for mercy. It’s interesting that they called Him “Master”, which is not something people address Jesus with often, if ever. More typical is “Teacher”, even among His disciples. Clearly these lepers are trying to exalt Jesus and humble themselves in the hopes that He will help them. Surely they have heard that He has healed lots of people before, possibly even other lepers.
It is also interesting that Jesus doesn’t heal them then and there. Instead, He tells them to go show themselves to the priest with the unspoken expectation that they will be cleansed by the time they get there. But as they all had faith that Jesus could heal them, they go in faith to see the priest. But then, one of them sees what happened, and turns back to praise God and thank Jesus, and this one was a Samaritan.
Jesus expresses disappointment, it sounds like, that the other nine did not praise God for their healing too. And then there’s a text note on the last thing He says to the man: instead of “your faith has made you well”, it might mean “your faith has saved you”. (v. 19) Considering that all ten lepers were healed, “saved you” makes more sense for Jesus to say to this one who came back. We don’t know what was in the hearts of the other nine, but this Samaritan was grateful for the mercy he was given, and responded appropriately.
Give us the faith that saves us, for we are sick and need Your mercy.