Writing at least two letters in any language constitutes the av melachah of kotaiv.1 Writing only one letter is still Biblically forbidden, but one is not punished for doing so. As we will see, the melachah of kotaiv encompasses far more than just writing with pen and paper. Any action which involves using something to create a letter or image2 that conveys some sort of meaning is forbidden, at least on a rabbinic level, on Shabbat.

Kotaiv in the Mishkan

The walls of the Mishkan were made from boards of acacia wood. To know exactly how the boards should be attached to one another, letters were marked on each board. The writing of these letters is the source for the melachah of kotaiv.3

What Is Included?

As with most melachot, some actions are Biblically forbidden under kotaiv and others are only rabbinically forbidden.4 On a Biblical level, one is only forbidden to write or draw using ink that is not easily rubbed out, on a surface where the ink will stick and not be smudged. All other instances fall under the rabbinic umbrella.5 For example, writing with one’s finger on a misty window or writing a name on a cake with icing. Etching an image onto a surface is also included in the Biblical prohibition,6 as is fixing an incomplete letter.7

Holding Together a Torn Piece of Paper

The Talmud says that if a person writes a letter on the edge of one piece of paper and another letter on the edge of a different piece of paper, he has violated kotaiv, even if those papers are not attached. Since the two papers could be joined together, the act of writing the letters is already kotaiv.8 This seems to indicate that the melachah of kotaiv is about writing two letters in a way that can be joined together, but combining existing letters – like a torn piece of paper — is allowed. As such, one may hold both sides of a torn piece of paper together and read from it. Some authorities9 disagree, so the best option10 is to hold the two pieces near one another so that one can read the words, but leave some space so that the words are not actually formed.11 Taping together two sides of a torn paper is forbidden according to all opinions.12

Books and Puzzles

A similar discussion arises regarding opening books that have words printed on the edges of the pages, breaking the writing apart when the book is opened and reforming the writing when the book is closed. The Levush and Magen Avraham maintain that closing such books on Shabbat does indeed transgress kotaiv, for when the book is closed the words on the outside are formed.13 Rama14 and Taz15 permit this, for two reasons: a) Books are regularly opened and closed, so forming words on the outside is not considered writing, as it is constantly being undone; b) As mentioned, joining letters or words that already exist is not considered kotaiv. The Alter Rebbe16 writes that the custom follows the lenient view.17 The same discussion would apply to putting together a puzzle on Shabbat.18

Page Numbers in Shul

The Magen Avraham19 writes that it is forbidden to attach a letter made from silver to a piece of material, because such an action contains an element of kotaiv. Even though when a letter has already been formed, kotaiv is not an issue according to most authorities, attaching it tightly to something else is forbidden. Based on this, Rabbi Moshe Feinstein ruled that the page number boards that are often placed in the front of a synagogue may only be used if the numbers are placed there in a loose way and can be easily removed.20

Doing or Discussing Business

The sages21 decreed that one should not conduct or even speak about business on Shabbat, lest it lead one to write things down.22 They also placed restrictions on lending out supplies on Shabbat because one may be tempted to write down the details of the loan.23

Common Activities to Avoid:

  • Children drawing pictures on a magnetic board.
  • Drawing pictures in the sand.
  • Building Lego in the shape of a letter.
  • Writing a person’s name in the icing on a cake or cookie.