“Rabbit rabbit white rabbit” is a common superstition, held particularly among children. The most common modern version states that a person should say “rabbit, rabbit, white rabbit” upon waking on the first day of each new month, and on doing so will receive good luck for the remainder of that month.
The exact origin of the superstition is certainly unknown, though it has appeared in print at least as early as 1420 in England, where it is most commonly said to have originated, though some reports place its origins even earlier, into the 1200s. Today it has spread to most of the English-speaking countries of the world, although like all folklore, determining its exact area of distribution is difficult. This superstition is related to the broader belief in the rabbit or hare being a “lucky” animal, as exhibited in the practice of carrying a rabbit's foot for luck.
Some have also believed it is representing a jumping into the future and moving ahead with life and happiness.