Don’t ask me why but I say it anyway just in case!
Some say it’s protection for the speaker from the other old saying “a pinch and a punch first day of the month”and it has spread to many English-speaking countries including the United States, particularly New England. I think that there was a folk tradition of wearing a rabbit’s foot for protection against evil. But if I start checking it out properly the day will be gone. Good Luck!
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