According to the Torah (Devarim 15:19-22), while a healthy firstborn animal must be sacrificed, if the animal has a mum – a blemish – it is lame, blind, or has “any ill blemish whatsoever,” the animal cannot be sacrificed, but can be eaten in an ordinary manner.
What is included in the category of a mum? What is considered to be “any ill blemish whatsoever”? Many of the rules that establish the definitions of these categories are traditions, some of which are subject to disagreements among the Sages. The sixth perek of Massekhet Bekhorot, which begins on today’s daf aims to respond to these questions.
The first example offered in the Mishna of a “blemish” deals with a wound to the ear. The Mishna teaches “if its ear was damaged and lacking from the ḥasḥus – the cartilage” it is considered a blemish, “but not if the skin was damaged.”
The term ḥasḥus, or, as it is used in modern Hebrew seḥus, appears in the Mishna as referring to parts of the body that are not soft like flesh or skin, but appear to be a type of soft bone. In modern terminology, this is dense connective tissues of which we find three types: Fibrocartilage, Hyaline cartilage and elastic cartilage, which is present in the outer ear and is the case discussed in our Mishna.
Rashi explains that the difference between an injury to the cartilage and to ordinary skin is that cartilage does not repair itself and is therefore considered a permanent blemish. While the commentaries agree that the ḥasḥus of our Mishna refers to the cartilage, not all agree on the exact intention of the Mishna. Some identify it with the tenukh mentioned in Sefer Shemot (29:20), which is defined as the middle protrusion in the ear, right next to the outer ear canal, explaining that animals have a similar structure inside of their ears. Many disagree, arguing that a blemish that is hidden in the body of the animal should not be considered a mum. According to their approach, the ḥasḥus refers to all parts of the ear that are thicker than ordinary skin.