Samaritans
Northern neighbours with their own temple and their own Pentateuch — and the reason "good Samaritan" was a jarring phrase.
After Assyria deported the northern kingdom it resettled the territory, and the population that emerged kept the five books of Moses but not the prophets, and worshipped on Mount Gerizim rather than in Jerusalem. By the first century the two communities avoided each other — John explains in an aside that Jews have no dealings with Samaritans, which is the only reason the conversation at the well is remarkable. The parable gets its force the same way: the listener is expected to flinch at the adjective, not the noun.
