This Fast is divided into two periods: (1) November 15th through December 19th
when the traditional fasting discipline (no meat, poultry, eggs, dairy, fish, wine,
and olive oil) is observed on Mondays, Wednesdays and Fridays, with katalysis for
wine and olive oil (some also permit fish) on Tuesdays and Thursdays, and for fish,
wine, and olive oil on Saturdays and Sundays, and (2) the period of the Forefeast,
December 20th through 24th, when the traditional fasting discipline is observed
Monday through Friday, with katalysis for wine and olive oil on Saturday and
Sunday. The eve of the feast, December 24th, is a strict fast day; December 25th
through January 4th is fast-free.