If you suddenly shudder or shiver, for no apparent reason, it is still likely that you will say that ‘someone has just walked over your grave’, meaning, of course, the site of your future grave. The first known written evidence for this notion is in Jonathan Swift's Polite Conversation (1738, i. 4). Occasional variations stipulate what it is that is doing the walking—a donkey or even, as suggested by the pimples associated with a shiver, a goose.
Opie and Tatem, 1989: 356.