The seven branches of the Menorah depend upon one another [i.e. if one is defective they are all invalid]. The seven lamps depend upon one another. The two passages of the mezuzah depend upon one another. And even one writing [i.e. word] affects them. The four passages in the tefillin depend upon one another, and even one writing affects them. The four fringes [of tzitzit] depend upon one another, since the four are a single mitzvah. Rabbi Ishmael says that the four fringes are four mitzvot.
Tractate Menahot (the plural of Minhah) deals with regulations regarding the meal offerings in the temple. Chapter 3 opens discussion of offerings which are done incompletely—Is there partial credit? Our mishnah extends the discussion to ritual objects—If they are lacking any part, can they still be used? In some cases (for example, wearing one of the tefillin), it is possible to have partial credit, but our mishnah identifies cases where it is all or nothing. Rabbi Ishmael’s position is rejected. In practice, if even one letter is missing from a scroll, it may not be used until it is repaired.