177. Using a Sefer for One’s Own Purposes
28:8 One should not make a cover for a sacred item out of something that was used for secular purposes. (One may do so for an object of a mitzvah that does not possess inherent holiness, e.g. a tallis bag. The Magen Avraham permits it in the case of a holy object providing that the form of the secular object is changed–Mishnah Brurah 147:13.) After the fact, if it was already done, it is permitted to use it. However, if the cover was made from something that was used for idol worship, it is forbidden even after the fact. 28:9 It is forbidden to use a holy book for one's own benefit, such as to provide shade from the sun or privacy from another person’s view. However, if one is trying to study Torah and the sun is too bright on his text, he may use another sefer to block the light. Similarly, one may place one sefer under another in order to raise it to a height that is more conducive to his studies. One may not, however, place one book inside of another in order to serve as a bookmark. One may not draw lines in a notebook on top of a sefer if the notebook has not already been used to take his Torah notes. Similarly, one may not place papers and other things inside a sefer for safekeeping.