Luke"s narration of this miracle focuses on the response of the Samaritan whom Jesus healed. It is not so much a story that he intended to demonstrate Jesus" divine identity, though it does that. It is rather another lesson for the disciples on an important attitude that should characterize them. [source][source][source]
"Not only is this narrative peculiar to Luke , but it also stresses several characteristically Lukan themes. Jerusalem is the goal of Jesus" journey (cr. Luke 9:51; Luke 13:33); Jesus has mercy on social outcasts; he conforms to Jewish norms by requiring that the lepers go for the required priestly declaration of health (cf. Leviticus 14); faith and healing should bring praise to God (cf. Luke 18:43; Acts 3:8-9); and the grace of God extends beyond Judaism, with Samaritans receiving special attention (cf. Luke 10:25-37)." [1][source]