Halakhah su Deuteronomio 6:9

Gates opening into courtyards and alleyways and cities and provinces, are required to have mezuzos, as it is said: "In your gateways."¹Deuteronomy 6:9.

Several Responsa serve as precedents for asserting that a man followed his regular routine.³⁰In addition to the sources that we discuss, see Teshuvot Igrot Moshe (E.H. 1:7). Rav Yitzchak Herzog (Teshuvot Heichal Yitzchak, E.H. 2:9:2) considers the possibility of partially relying on a husband’s patterns to determine that a man was at a particular place where a bridge collapsed into the water.³¹Although a pattern is sometimes called a “chazakah,” it is a very different concept than the chazakah that we mentioned earlier, which referred to the assumption that the status quo has been maintained. He notes that the Taz (Yoreh Deah 69:24) rules that if a woman is unsure if she salted a piece of meat before she cooked it, she may assume that she followed her normal pattern of salting the meat. As a precedent, the Taz cites the Gemara’s ruling (Berachot 16a) that if one is reading the Shema and is unsure if he has read the verse of “Uch’tavtam” from the first section of Shema or the second section, the doubt is resolved if he had begun to read the verse of “L’ma’an yirbu,” which follows “Uch’tavtam” in the second section (see Devarim 6:9 and 11:20-21). Since people normally recite Shema in the proper order, a person may assume that he followed his usual routine and proceeded to the next verse of the second section because he had recited everything until then.

To affix a mezuzah on entrances: To affix a mezuzah on the doorposts of our homes, as it is stated (Deuteronomy 6:9), "And you shall write them on the doorposts of your house and on your gates." And the content of the mezuzah is that we write two sections of the Torah on one parchment - and they are 'Hear Israel,' until 'and in your gates'; [and] 'And it shall be if you listen,' until 'upon the earth.' And we affix them to the doorposts of the opening of the house.