Thought I'd use this space to organize my thoughts on Samaritans in the Gospel of Luke. What follows will not be revelatory.
First, while I knew there was enmity between Samaritans and Jews—once one people, then rival sects after the division of the Davidic kingdom—and while I'd read that the history of Samaria was as heartbreaking Judea’s, with their land being decimated by Assyria, their survivors barred from worshiping with exiled Jews upon their return from Babylon—I did not know that, in the time before Jesus' life, hostilities between Jews and Samaritans bubbled over into violence. In a visceral way, Jews and Samaritans hated one another. They also worshiped the same God and had a common religious and national history.
Samaritans show up three times in Luke's Gospel. First in chapter nine when a Samaritan village does not welcome Jesus because he had "set his face to go to Jerusalem." The apostles James and John are good sectarians and ask Jesus if they should pray for fire to "consume," i.e., kill the Samaritans. Jesus rebukes the brothers.
The next time we hear from a Samaritan is in the eponymous parable. A lawyer asks Jesus "What must I do to inherit eternal life?" Jesus tells the lawyer that he already knows, which prompts the pious man to recite the Shema and then he—not Christ—adds "and [love] your neighbor as yourself." The lawyer follows up with "who is my neighbor." We know what happens next: Jesus tells a parable and concludes by asking who was neighbor to the half-dead man in the ditch. The priest and Levite failed at neighborliness, and this must have greatly offended the lawyer and anyone listening. As New Testament scholar Matt Skinner points out, in answering, the lawyer cannot even bring himself to say the word “Samaritan,” his antipathy runs that deep. He says simply that the neighbor was he "who showed…mercy."
Samaritans show up one last time in chapter 17. Jesus walks "through the region between Samaria and Galilee" and encounters ten lepers. These call Jesus master and beg him to have mercy. Jesus does, but only one leper shows gratitude after the healing. Just one praises God, and he does so uninhibitedly, with all his heart, soul, and strength; he "[praised] God with a loud voice. He prostrated himself at Jesus feet and thanked him. And he was a Samaritan." (Now that is dramatic pacing.) The others, who did not give thanks, are presumably Jesus’ kindred.
What to glean from this? Here's what I have at the moment.
We are often most cruel to those who worship the same God, are part of our Christian tradition, part of the koinonia (which Paul insists must not be broken)
We mock or call out others for not worshiping correctly, not pleasing God or loving God (because of their theological lens, dogma, doctrine, liturgy); it might be their worship, their acts, their love that is authentic. It might be ours that is faulty or wrong or unhelpful, or worse.
Our perceived rival—the threat to our one true religion/faith—is our neighbor and is pleasing to God. We are not pleasing to God.