The gospel text is the parable of the good Samaritan. Here is the reading:
Just then a lawyer stood up to test Jesus. “Teacher,” he said, “what must I do to inherit eternal life?” He said to him, “What is written in the law? What do you read there?” He answered, “You shall love the Lord your God with all your heart, and with all your soul, and with all your strength, and with all your mind; and your neighbor as yourself.” And he said to him, “You have given the right answer; do this, and you will live.”
But wanting to justify himself, he asked Jesus, “And who is my neighbor?” Jesus replied, “A man was going down from Jerusalem to Jericho, and fell into the hands of robbers, who stripped him, beat him, and went away, leaving him half dead. Now by chance a priest was going down that road; and when he saw him, he passed by on the other side. So likewise a Levite, when he came to the place and saw him, passed by on the other side. But a Samaritan while traveling came near him; and when he saw him, he was moved with pity. He went to him and bandaged his wounds, having poured oil and wine on them. Then he put him on his own animal, brought him to an inn, and took care of him. The next day he took out two denarii, gave them to the innkeeper, and said, ‘Take care of him; and when I come back, I will repay you whatever more you spend.’ Which of these three, do you think, was a neighbor to the man who fell into the hands of the robbers?” He said, “The one who showed him mercy.” Jesus said to him, “Go and do likewise.”
It's a well-known story, obviously. We have a Samaritan, a member of the fringe-like group in Judea who accepted only the Torah (the first five books of the Hebrew Bible) and had their own version of the canon, known as the Samaritan Pentateuch. The Samaritans consider themselves to be the survivors of the destruction of the northern kingdom, who remained in the land continuously. Their practices were different from that of other Jews — particularly when it came to Jerusalem, the center of Jewish worship. Samaritans centered their religion on Mount Gerizim instead. All of this meant that other Jews looked down on the Samaritans, claiming they were not truly part of the people of Israel.
Here, however, the Samaritan is the protagonist. When the best of the best, a priest and a Levite, pass by the man in need, the Samaritan stops, cares for him, and even pays for his lodging. The point of the parable, on the basic level, is that the concept of "neighbor" does not depend on group loyalties or titles, but on loving action.
When I read this parable again today, another aspect of the story struck me. According to Luke, the lawyer is seeking to "justify himself" when he asks, "Who is my neighbor?" The lawyer knows the law; he knows that he is supposed to love his neighbor. When he asks this self-justifying question, he is clearly focused on himself. In other words, the lawyer seems to be thinking to himself, "I love my neighbor. Clearly, I am fulfilling the law and will inherit eternal life." However, Jesus frames the story differently. The man going down from Jerusalem to Jericho is the character with whom the lawyer is supposed to identify; the question "Who is my neighbor?" has been turned into "Who is this man's neighbor?"
The twist in the parable is this: the man's neighbor is not the one for whom he cares. The man's neighbor is the one who cares for him. It's not about what great things the man (and, by extension, the lawyer) is doing. It's about the care he receives when he is in need. Jesus is not only subverting the expectations about Samaritans and priests and Levites. Jesus is also subverting the expectations about what it means to be a neighbor. At the beginning of the reading, "neighbor" is understood as the one I love. By the end, "neighbor" is understood as "the one who showed [me] mercy." It's no longer about the I, but about the other.