The Vulcan greeting is based upon a blessing gesture used by the kohanim (koe-hah-NEEM) during the worship service. The kohanim are the genealogical descendants of the Jewish priests who served in the Jerusalem Temple.
The blessing gesture forms the hand into the shape of the Hebrew letter Shin, which stands for Shaddai, a name for God.
Like most Jewish children, young Leonard Nimoy could not contain his curiosity about what the kohanim were really doing up there in front of the congregation. He writes:
“The special moment when the Kohanim blessed the assembly moved me deeply, for it possessed a great sense of magic and theatricality… I had heard that this indwelling Spirit of God was too powerful, too beautiful, too awesome for any mortal to look upon and survive, and so I obediently covered my face with my hands. But of course, I had to peek.” (From his autobiography, I am Spock.)
Nimoy felt that there should be some kind of distinctive greeting among Vulcans, analogous to a handshake or a bow. Alan Dean Foster’s novelization, based on an early script, has Spock kneeling before the Vulcan matriarch, T’Pau, who places her hands on his shoulders, like royalty dubbing a knight. But Nimoy didn’t care for this. Previous episodes had already established that Vulcans are touch telepaths. Therefore, a touch on the shoulders would be an invasion of privacy. Instead, Nimoy drew upon his own Jewish background to suggest the now-familiar salute.
Full article here, via Metafilter.
The thing is, not everyone can make the Shin gesture. Nimoy himself had to practice as a child, and apparently neither William Shatner, nor Zachary Quinto- who plays Spock in the 2009 movie- can hold the gesture. I actually suspected that Quinto had a little help to form his salute- his hand seemed strained and weirdly angled in every scene where he had to throw down the old LLAP. Turns out that Shatner tied his fingers together with fishing line; Quinto used superglue.
Umm, you guys, this begs the question….
WHY DID NOBODY SUGGEST THAT THEY USE….
There’s some more Pageslap Star Trek fun here.
Hey what do the Kohanim play in the winter?