DEUT278 It is a positive commandment to affix a m'zuzah at the entrance of the home as Scripture states, And you shall write them on the doorposts of your house and on your gates [this verse]. In the m'zuzah [a rolled-up piece of parchment generally enclosed in a case] two sections of Scripture are written: Hear (ibid. 4-9); And it shall be if you hearken (ibid. 11:13-21). A person has a duty to take care about a m'zuzah, so that every time he enters or leaves he will encounter the unity of the God [written in the m'zuzah] and will remember his love for Him, and so he will awaken from his slumber and his errors in the vaping, empty matters of the present; and he will realize that nothing endures forever and ever except a knowledge of the Divine Rock-foundation of the world [God]. So he will return at once to his good sense and walk in the straightforward paths of decency.