151. More Types of Errors

24:3 If two letters are found joined together, if it seems that they became joined after the section was written, the sefer Torah may be used so long as the shape of the letters was not changed. If the letters appear to have been joined when the section was being written, different procedures apply. If the letters were joined before the letter was completed, such as a final Nun connected in its middle, then the sefer is pasul (unfit for use). However, if – on a weekday – one can rub off the excess ink, thereby separating the letters, the sefer Torah is fit. If the letters became joined after the writing of the letter was completed, the Torah is fit for use.

24:4 If a letter is found to have lost its shape, whether it was originally written this way or whether it occurred afterward, such as from a hole, the Torah may not be used. If a hole is found inside or outside a letter so that the letter’s shape is unaffected but it is not completely enclosed by blank parchment, if it is obvious that the hole was made after the letter was written, then it is kosher. (In a case of doubt, we assume the hole was made after the section in question was written - Mishnah Brurah 32:55.) If the ink faded from a letter so that it is no longer fully black, the scroll may not be used. (Some permit the use of a Torah whose color has faded from age - Mishnah Brurah 143:25.)