Well, yes and no. I mean, it's not like those other neighborhoods you mentioned were filled with nature-worshipping heathens who dance naked around oak trees on Midsummer's Eve or anything. That description really only applies to Fox Chapel. And neither Bethel Park nor Mount Lebanon was founded as a spiritual retreat -- which is just as well, since a large population of monks seeking enlightenment would probably hurt business at South Hills Village mall. And then where would we be?
Like a lot of places -- including Munhall and the Cayman Islands -- Bethel Park was created mostly as a tax dodge. It seems fitting to me, somehow, and even now its officials are proud of the fact. The municipality's own Web site (www.bethelpark.net) boasts that farmers in the South Hills "who felt overtaxed sought to have their own township -- thus, the courts granted a charter in 1886 creating Bethel Township." Indeed, the place still votes Republican to this day.
The "Bethel Park" name itself, though, probably does have an explicit religious connection. The name appears to have been inspired by the Bethel Presbyterian Church, whose history, according to Franklin Toker's Pittsburgh: An Urban Portrait, dates back 100 years farther than the borough itself. The church was founded during the Revolutionary War, and its modern building can still be found today on the aptly named "Bethel Church Road." (We can only assume that what the Bethelites of pioneer days lacked in originality, they made up for in piety.) The town's name was changed to "Bethel Park" in the mid-20th century. A brief history recently reported in the Pittsburgh Post-Gazette surmises that the name change was carried out to distinguish the area from other Bethels in the eastern part of the state, but I find this hard to believe: How could anyone confuse Bethel Park's one-of-a-kind suburban charm with anyplace else?
Mount Lebanon's name is a bit easier to suss out. According to several municipal histories I've seen, the place takes its name from two trees planted in 1850 in the yard of one Rev. Joseph Clokey. The trees were cedars of Lebanon, a type of broad-branched pine tree that grows in the Middle East. The same type of tree appears on the flag of Lebanon itself, and Clokey's trees were reportedly transplanted directly from what was then known as Palestine. In a way, the trees were a fitting totem for a community that, a half-century later, would be populated by families who'd uprooted themselves for a quieter life in the suburbs. (Cedar Boulevard, one of the municipality's thoroughfares, likely takes its name from Clokey's trees, too, as does nearby Cedar Lake.)
So in a way, you're only half right: While the community owes its name to the actions of a minister, Mount Lebanon arguably has a "nature-oriented name" as well.
Just don't tell anyone from Bethel Park: The South Hills are rife with sectarian tension, as everyone knows, and we don't want to touch off any holy wars.