A traditional custom in Japan, and among many Japanese Americans include the “san-san-kudo” sake sharing tradition, which translates to “three sets of three sips equal nine.” Three is an indivisible number, and it is considered a sacred number in Buddhism.
Image Via The Knot
The groom starts with the smallest of three cups and takes three sips from the cup and then the bride follows. After the groom proceeds with the middle size cup taking again three sips and then goes to the large cup, and the bride follows the same system. At the end of the sharing of sake toast ceremony the families of both bride and groom drink a cup of sake to signify not only the union of bride and groom but also the unity of two families.