Today is a strict fast day in remembrance of the violent style of execution of God's greatest prophet, St. John the Forerunner. Though this commemoration is an ancient one, the prescription for a strict fast day is relatively recent as it does not appear in the old typika (rules of practice). Pious Orthodox people have established certain customs therefore to further remember and honor the honorable Forerunner.
1. Avoid using a round plate, since the head of the Glorious Prophet was delivered on a plate to Herodius.
2. Avoid dancing, since a dance seduced Herod to give even half of his kingdom to his seductress Salome, though this gave her the opportunity to ask for the head of the Glorious Prophet.
3. Avoid birthday celebrations, since the tragedy took place during the birthday celebration of Herod (postpone for another day).
4. Avoid cabbage, since it is round like a head and according to legend cabbage leaves were placed beneath St. John's head on the day that he was beheaded. This legend may have arisen specifically because of the shape of the cabbage.
5. Avoid eating round food, such as apples, pears, onions, garlic, or in general any round fruits or vegetables on this day. This is because of their similarity to the human head.
6. Avoid red wine, because red wine resembles the blood (except that of Holy Communion).
7. Avoid knives, so as not to cut or chop anything, for obvious reasons.
Read also: St. Justin Popovich: The Beheading of John the Prophet and Forerunner