According to the law, a mezuzah must be inspected twice every seven years. Even if the mezuzah is found to be perfectly kosher, according to the great kabbalist the Ariza”l, in a time of trouble it is beneficial simply to read the text of the mezuzah aloud with a tune according to the musical notes of the Torah.
One may ask why, once a mezuzah is checked and found kosher, we need to check it again periodically. Besides the obvious material reasons – that a mistake may not have been noticed before, or that with time ink can crack and letters can break rendering a mezuzah non-kosher – there are reasons rooted in the esoteric. Some say, for example, that a mezuzah can change with time, not from the effect of the elements but through the influence of the people who live in the house, their behavior and the atmosphere they create in their home. There are some among Sefardic Jews who claim that they can read a mezuzah like the palm of a hand, telling much about the people of the house. Some rabbinical authorities, however, do not approve of this practice.
We influence the mezuzah and the mezuzah influences us. To keep this relationship happy, we must check the mezuzos and check ourselves. It has therefore become a universal custom among Jews to inspect their mezuzos during the month of Elul, the last month of the year before the Day of Judgment - Rosh Hashanah. This is a time of teshuvah, repentance, of introspection, of self-inspection, and, thus, the time to check the mezuzos.
Slant of the Mezuzah
The mezuzah is placed slanted midway between vertical and horizontal, with the top of mezuzah tipped counterclockwise when facing the mezuzah (so that the mezuzah points to the room being entered when the mezuzah is on the right). According to Rashi, the mezuzah should be placed vertically, but according to Rabbeinu Tam, horizontally. Most Sefardic communities follow R. Yosef Karo’s ruling and affix the mezuzah vertically, according to Rashi’s opinion. In Ashkenazic communities, however, the accepted way is a compromise between the two opinions.
The root of the disagreement between Rashi and Rabbeinu Tam is the translation of the Hebrew word “nagar”. The Talmud states that the mezuzah affixed in such a way that it resembles a “nagar”, is invalid. Literally, nagar means a bolt or a door latch. Rashi interprets this word to mean a side-bolt, from which it follows that because a mezuzah affixed horizontally resembles a side-bolt it is invalid. Accordingly, Rashi rules that the mezuzah may not be affixed horizontally, but rather it should be affixed vertically, so that a person passing by may read the text. Some Sefardim, in accordance with this opinion, do not roll the mezuzah parchment but actually affix it flat on the doorpost so that it can be read by anyone passing through the doorway.
Rabbeinu Tam disagrees with Rashi, interpreting the word nagar to mean a vertical bolt. According to him, because a mezuzah affixed vertically resembles a hinge-bolt, it is consequently invalid. He writes further that to affix the mezuzah vertically would be disrespectful, similar to burying a person vertically. Rather, a mezuzah should be placed horizontally just as the Tablets were placed horizontally in the Holy Ark.
Shulchan Arukh and Gra rule according to Rashi, while the Rema sides with Rabbeinu Tam. Rema reports the position put forth in Tur and Maharil that those who are particular in Mitzvos (ha-medakdekim) satisfy both opinions by placing the mezuzah at a slant. This has become the universal custom among Ashkenazic Jews.
One may wonder: if the opinion of Rashi was to affix the mezuzah vertically, and that of Rabbeinu Tam was to do so horizontally, placing the mezuzah at a slant, neither vertically nor horizontally, is contrary to both opinions! However, the opinion of Rashi was that the mezuzah affixed horizontally is invalid. Similarly, the opinion of Rabbeinu Tam was that the vertically affixed mezuzah is invalid. Since a diagonal position is neither vertical nor horizontal, neither Sage would disqualify the mezuzah affixed in such a way.
This compromise is not coincidental. The Kabbalah teaches that there are three general categories: thesis, antithesis and synthesis. The first two are limited by definition, as opposites negate one another. (In our case, that which is vertical cannot be at the same time horizontal). However, the third, middle way is infinite, as it includes both opposites and is not limited by either one. The mezuzah elicits a revelation of G-dliness of an infinite nature – the infinite Encompassing Light that leaves no room for the forces of evil. It may be suggested that the compromise diagonal position of the mezuzah is in accordance with the infinite light that radiates through it.
