Analysis: "The Licked Hand" is another handwriting-on-the-wall tale in the same vein as "Aren't You Glad You Didn't Turn on the Light?" and "Welcome to the World of AIDS."
The trope derives from a Bible story (book of Daniel) in which a feast thrown by the pagan Babylonian King Belshazzar is interrupted by the specter of a disembodied hand scrawling a cryptic message on the wall. As ultimately interpreted by the prophet Daniel, the message conveys God's judgment, predicting the downfall of Belshazzar and his entire kingdom. To "read the handwriting on the wall" is to foresee one's own impending doom an apt and chilling metaphor.
Note that the chain-letter format (third variant on previous page) does little to enhance the impact of the story; in point of fact, the directive to "pass this along or die" undermines the narrative by transporting it to a fantasy realm where murderous madmen are capable of stalking their victims via forwarded email. That aside, the email retelling follows a tried-and-true formula, and works.
Variants of "The Licked Hand" were being collected by folklorists as long ago as the late 1960s. Indeed, the chain-letter version appears to have been cribbed from a 1967 oral transcription published in Ronald L. Baker's Hoosier Folk Legends (Indiana University Press, 1982). As in the later variant, the events were said to have taken place near a small town called Farmersburg, though there were two female protagonists instead of one, and the note left by the murdering madman read as follows:
"I'm coming to see you. I had my chance once before, but I didn't take it. Not only dogs can lick."
This is the very definition of a cautionary tale.

