On Yom Kippur, the Torah instructs us to "afflict" ourselves, which means abstaining from an assortment of physical pleasures. There are two reasons for this: a) On this day, when our connection to G‑d is brought to the fore, we are compared to angels, who have no physical needs. b) We afflict ourselves to demonstrate the extent of our regret for our past misdeeds. (Click here for a more mystical explanation.)

Instead of focusing on the physical, the majority of the day is spent in the synagogue, devoted to repentance and prayer.

There are five areas of pleasure that we avoid on Yom Kippur—from sundown on the eve of the holiday until the following nightfall (click here to find out when Yom Kippur starts and ends in your location):

  1. Eating or drinking.
  2. Wearing leather footwear.
  3. Bathing or washing.
  4. Applying ointment, lotions, or creams.
  5. Engaging in any form of spousal intimacy.

(These all are restrictions unique to Yom Kippur; we also abstain from all creative activities forbidden on the Shabbat, e.g., turning on lights, driving, and carrying in the public domain.)

We are compared to angels, who have no physical needsIt is also customary not to wear gold jewelry on Yom Kippur, as gold is reminiscent of the sin of the Golden Calf, and on the Day of Atonement – the day when we were forgiven for that egregious sin – we do not want to "remind" the Prosecutor (Satan) of our past sins.

Fasting:

  • All adults over bar or bat mitzvah fast, including pregnant or nursing women.
  • Healthy children should be educated to fast for a short amount of time, starting from the age of nine. They shouldn't be given to eat after sundown on the eve of Yom Kippur, and their breakfast should be slightly delayed.
  • Fasting on Yom Kippur is of utmost importance. This is true even if in order to fast a person must spend the entire day resting in bed, and will miss synagogue services.
  • Someone who is ill, a woman who has recently given birth, an individual who needs to take medication, or a person of advanced age who feels it difficult to fast should consult with a rabbi.

Someone who upon a rabbi's instructions (based on the recommendation of a medical professional) needs to eat on Yom Kippur need not be dejected. The same G‑d who made it a mitzvah for healthy people to fast on Yom Kippur also commanded that preservation of life and health is even more important than fasting. The healthy person fulfills a mitzvah by fasting; the ill person does a mitzvah by eating.

An ancient High Holiday prayerbook suggests that an ill person recite the following prayer before eating on Yom Kippur:

Behold I am prepared to fulfill the mitzvah of eating and drinking on Yom Kippur, as You have written in Your Torah: "You shall observe My statutes and My ordinances, which a man shall do and live with them. I am G‑d." In the merit of fulfilling this mitzvah, seal [my fate], and [that of] all the ill of Your nation Israel, for a complete recovery. May I merit next Yom Kippur to once again fulfill [the mitzvah of] "you shall afflict yourselves [on Yom Kippur]." May this be Your will. Amen.

Click here for more information on this topic.

Leather Footwear:

The healthy person fulfills a mitzvah by fasting; the ill person does a mitzvah by eatingWe don't wear shoes or slippers if they contain any leather at all—whether in their uppers, in their soles or heels, or in an insert.

The prohibition applies to footwear only. Wearing a leather belt, kippah, or jacket presents no problem whatsoever.

Children, too, should be taught to wear non-leather footwear.

Washing and Bathing:

The prohibition against washing or bathing applies whether using hot or cold water, and even to washing only part of one's body. In the words of the Sages: "Even to insert a finger in cold water is forbidden."

Nevertheless, there are several exceptions to this rule. They are:

  • It is permitted to wash hands upon exiting the lavatory.
  • It is permitted to wash any area of the body that has become soiled.
  • Upon awakening in the morning, one performs the ritual hand washing—but washes only until the knuckles.
  • Before they administer the Priestly Blessing, the priests' hands are ritually washed in the normal fashion.
  • It is permitted to wash one's hands before handling food.
  • Someone who needs to bathe or wash for health reasons should consult a rabbi.