One letter out of place in the Torah destroys the entire universe

"Rabbi Ishmael said to me, ‘My son, what is your occupation?’ I told him, ‘I am a scribe’, and he said to me, ‘Be meticulous in your work, for your occupation is a sacred one; should you perchance omit or add one single letter [in preparing a Torah scroll], you would thereby destroy all the universe’."

-- Talmud Bavli, tractate Eruvin 13a



To better understand this quotation from the Talmud, please read this page on the rigors of preparing a Torah scroll:



Making a Torah Scroll - How is it made?

Some highlights:

• There are 304,805 letters in a Torah Scroll.
• Each page has 42 lines.
• The Torah Scroll must be written by a specially trained pious scribe called a sofer.
• It takes about a year to write an entire Torah Scroll.
• Even a single missing or misshapen letter invalidates the entire Sefer Torah. [!!!]