Unpacking the Gematria of 18

Many Jews typically give charity (and gifts) in multiples of 18 (e.g. 18, 36, 54, 72 etc.). On a simple level, this is because the numeric value of the Hebrew word חי (chai), which means “life,” is 18. We are thus symbolically blessing both the recipient and the giver with good, long lives.

Who Started It?

It isn’t clear when or where this custom originated, but one classic example dates back to the 1700s when, on multiple occasions, the Baal Shem Tov instructed people to donate in multiples of 18, using the term chai.1

The Price of a Sheep

An earlier source for donating 18 coins is found in the Code of Jewish Law2 (and quoted in Tanya3): one who transgresses a sin which would have required an animal offering during the Holy Temple era, should donate 18 peshitim (coins) to charity.

In this case, there is no significance to the number 18 beyond the fact that 18 peshitim was how much a run-of-the-mill sheep would have cost back then.4 Nonetheless, some look to it as precedent for giving in multiples of 18, since nothing in our lives is truly happenstance.5

The Significance of 18

The Talmud6 and Midrash7 list many things that are specifically in the amount of 18 or chai:

  • Our forefathers, Abraham, Isaac, and Jacob, are mentioned together in the Torah 18 times.
  • There are 18 passages in which G‑d communicates with Moses and Aaron as equals.
  • G‑d’s name appears 18 times in the Shema.
  • There are 18 “commands” in the Torah regarding the building of the Mishkan (Tabernacle).
  • G‑d’s name appears 18 times in Psalm 29.
  • There are 18 vertebrae in a person’s spine.

In fact, these are the reason the Sages instituted that the daily Amidah should consist of 18 blessings.

Rabbi Yehuda Lowe, the Maharal of Prague, further explains that this number is associated with the Divine attribute of mercy.8 The additional (19th) blessing, in which we ask G‑d to judge our enemies, is not included in the 18, which are all about mercy, blessing and life.9

Additional Significance

The mystics point out that 18 is also the numeric value of chessed (kindness), osher (wealth) and kofer (atonement), when one uses the system of mispar katan, in which all zeroes are removed.













This reflects the three primary motivations for giving charity: to merit Divine kindness, achieve atonement for a misdeed, or as the Talmud10 tells us, to merit an abundance of livelihood.

Just Give!

At times, the Rebbe would advise giving in various other increments, depending on the circumstances. Overall, the main thing is to give as much as you can, providing as much assistance to others as you are able. For charity, no matter the amount, has the ability to save us from danger, and in its merit we will usher in the Ultimate Redemption, may it happen imminently.