In today's Gospel, a lawyer asks Jesus two crucial questions: First, he asks, "Teacher, what must I do to inherit eternal life?" Jesus encourages the lawyer to answer the question by referring to the command to love God and neighbor. Second (perhaps to justify himself for not treating everyone as his neighbor), he asks, "And who is my neighbor?" In response to that question, Jesus tells the parable of the Good Samaritan.
Looking carefully at the parable, we see it doesn't answer the question, "Who is my neighbor?" Instead, it seems to answer another question, "Which of these three proved himself to be a neighbor?" The parable explains what it means to be a genuine neighbor. Jesus implies that being a neighbor to others is more important than defining who my neighbor is. The lesson is that everyone is my neighbor.
We could say that the answer to the lawyer's first question ("What must I do to inherit eternal life?") is to be a good neighbor. If you want to know what it means to be a neighbor, look at the Samaritan. The priest, Levite, and Samaritan noticed the wounded man by the roadside. What set the Samaritan apart is that he responded to what he noticed.
The priest and the Levite probably saw with eyes focused on the laws of purity, which they saw as more important than showing compassion. Their way of seeing precluded offering assistance to the man on the road. The Samaritan's way of seeing gave way to compassion and mercy. It is the kind of seeing that characterized Jesus Himself. His answer to the lawyer's first question is, "Be a good neighbor in the way that I am."