ויקרא, פרק י״א, פסוק כ״ו

The laws of ritual impurity extend to animals that possess only partial signs of purity or lack them entirely. The primary approach among commentators is that the focus here is not on the dietary prohibition against eating these creatures, but rather on the impurity transferred by touching their carcasses.

The criteria for these impure animals include having a hoof that is not completely split. Most commentators explain this refers to creatures with a solid, round hoof resembling a shoe, such as horses and donkeys [רשב״ם, שד״ל, רלב״ג, ביאור יש״ר, ביאור שטיינזלץ, רד״צ הופמן]. Another perspective suggests the hoof might be split at the top but remains connected at the bottom, as seen in the camel [רש״י, גור אריה]. Additionally, these animals do not chew their cud, a trait exemplified by the pig [רלב״ג].

The rules concerning these creatures establish specific guidelines for how impurity is transferred. Different parts of the same animal carcass can combine to reach the minimum physical size required to convey impurity [מלבי״ם, צפנת פענח, ברטנורא]. Furthermore, the scope of this impurity is broad, applying to a limb torn from a living animal and even to a fetus still developing inside the mother's womb [מלבי״ם, צפנת פענח, אדרת אליהו].

Although the impurity of animal carcasses is addressed elsewhere, its reiteration serves crucial purposes. First, it clarifies that ritual impurity only takes effect after the animal has died, firmly rejecting the misconception that these creatures are impure while still alive [אבן עזרא]. More importantly, it highlights a fundamental distinction between pure and impure animals regarding ritual slaughter. When a pure animal undergoes proper slaughter, the process prevents it from conveying carcass impurity, even if the animal is later found to have a fatal physical defect. In stark contrast, ritual slaughter has no purifying effect on an impure animal. It will transfer impurity regardless of whether it died a natural death or was intentionally slaughtered [רש״י, רשב״ם, מזרחי, שפתי חכמים, חזקוני, גור אריה, פרדס יוסף]. This emphasis is particularly necessary because some of these animals possess hooves and superficially resemble pure animals, which could lead to the mistaken assumption that ritual slaughter might somehow purify them [העמק דבר]. In reality, the impurity takes hold immediately, applying even in the moments while a slaughtered impure animal is still twitching [מלבי״ם].