150. An Error in a Sefer Torah
24:1 If we find a serious error in a Torah that's the fault of the sofer (scribe), we may not read from that Torah and must take out another. Such errors from a sofer include: an extra letter; a missing letter; letters substituted in such a way that it affects pronunciation, such writing "tumim" (as in "urim v'tumim") as "t'umim" ("twins"), or writing mig’r’sheihen ("their grounds" in the feminine) as mig’r’sheihem (in the masculine). Similarly, if the error affects the meaning, even though the pronunciation might not be changed; this would be the case in Exodus 25:10 if the sofer spelled rochvo ("its width") RChVH instead of RChVO (ending the word with a Hei instead of a Vav, making it feminine instead of masculine). The letter Veis might take a cholam (the "O" sound) as its vowel, so the word could still be pronounced "rochvo," nevertheless, but it is still considered a major error. If, however, a scribal error changes neither a word's meaning nor its pronunciation, another Torah need not be taken out. Examples of this type include adding or deleting the letter Vav or Yud to words that might take it or leave it. (This is also true if letters that should be written smaller or larger than usual, such as the Alef in Leviticus 1:1 or the Ayin and Daled in Deuteronomy 6:4, are written normal-sized, or regarding the dots over the word “ayei” in Genesis 18:9 and other things that are known from tradition - Mishnah Brurah 143:27.) The reason for this is that writing a Torah is subject to human error. We can´t know for a fact that another Torah will be free of such imperfections. However, if the Torah is missing a Yud that is part of a word's root, it is considered a major error and another Torah must be used. An example of this would be Genesis 21:17, "What distresses you, Hagar?" If the first yud is left out of the word “tiri,” it would mean "What do you see, Hagar?"
24:2 More major errors include: if word is spaced so that it appears to be two words, or if two words are spaced so close that they appear as a single word (to a child of average skill – Mishnah Brurah 143:25); if an extra word is included, whether it is a word that belongs there written a second time or a word completely out of place; if a closed section was written open or vice versa; if a section was divided in the wrong place or if a division between sections is omitted. In all these cases, another Torah must be taken out and read.