The Gemara on this daf discusses the bigdei kehuna – the special uniform worn by the priests who are involved in the Temple service – and particularly the respect and honor that these clothing deserve.
Rahava said that Rav Yehuda said: One who intentionally tears any of the priestly vestments transgresses a prohibition and is flogged, as it is stated concerning the robe: “It shall have a hem of woven work around the opening of it, like the opening of a coat of mail, and it shall not be torn” (Shmot 28:32). Just as it is prohibited to tear the opening of the robe, so too, it is prohibited to tear any of the priestly vestments. Rav Aha bar Ya’akov strongly objects to this: But perhaps this is what the Merciful One is saying in the Torah: An opening should be made in order that it not tear. In other words, the Torah was giving an explanation, not a prohibition. The Gemara rejects this: It is written: In order that it not be torn? Clearly, the intention of the verse is to state a prohibition.
The Sefer Ha-hinukh explains the prohibition as stemming from the heightened respect that needs to be shown to the priestly uniform, both by kohanim and by the general population. Some commentaries distinguish between the me’il (outer garment) – where the prohibition applies to any tear – and the other
bigdei kehuna, where the only prohibition is when the tear was made in a destructive manner.
Rabbi Moshe Galanti points out in his Sefer Korban Hagiga that it is unusual for the Talmudic sages to interpret a passage that is clearly an explanation of a commandment and understand it to be a prohibition. For example, when the Torah commands a Jewish king to refrain from marrying too many wives, concluding “and his heart will not be swayed,” it is not understood as a separate prohibition, forbidding the king from turning away; rather, it is interpreted as an explanation of why too many wives is a bad thing.
One suggestion put forward by the commentaries (see Rashi on the Torah) is that this case is unique because the Torah repeats the same words in both the commandment to make the bigdei kehuna and the description of the fulfillment of that commandment. It is difficult to accept that the Torah would give
the same explanation twice, particularly in the case where the Torah is describing that the garments were being made. Thus it is understood to be teaching a law, rather than simply offering an explanation.