The seven branches of the Menorah are all essential to one another, that is, if one of the branches is missing, the entire Menorah is invalidated. The seven lamps on top of the Menorah are essential to one another.
The two passages written in the mezuzah scroll are essential to one another, and even the proper writing of one letter is essential to the validity of both passages. In describing the mezuzah, that Torah says, “and you will write these words” (ktavtam) which can also be understood as “ktav-tam,” “perfect writing,” meaning that every letter should be perfect.
The Menorah was to be produced from a single block of raw material, and it would be made of gold. If the craftsman made it out of scraps of gold, the Menorah is invalid. In describing the Menorah, the Torah said that it must be “hammered out.” An additional word “being” indicates that this requirement is essential. However, if the Menorah was made of other kinds of metals, then it did not have to made out of one piece, and was nevertheless valid.
Art: Etching of the Lighting of the Menorah, by a Dutch Artist, 1705