Ash Wednesday and Good Friday are obligatory days of universal fast and abstinence. Fasting is obligatory for all who have completed their 18th year until the beginning of their 60th year. Fasting allows a person to eat one full meal. Two smaller meals may be taken, not to equal one full meal. Abstinence (from meat) is obligatory for all who have completed 14th year of age. Read the whole article for more information about fasting.