As we learned on yesterday’s daf the focus of the Gemara in the fifth perek is to determine what an animal can carry on Shabbat. Specifically, which of the items that one customarily places on an animal – a saddle, reins, and chains – are considered a “garment” for the animal? Generally speaking, if they serve the animal’s needs, it is permitted to place them on the animal. But which items are considered a burden that would be prohibited to be placed on an animal?
On today’s daf ,the Gemara attempts to clarify this question by turning to a different area of halakha. A para aduma – a Red Heifer – cannot be used for the purification ritual if it had been subjected to work, e.g. if a yoke had been attached to it. The Gemara teaches:
If its owner tied a red heifer with its reins that are attached to the bit, it remains fit for use in the purification ritual. And if it should enter your mind to say that a bit is considered a burden, why does a red heifer remain fit for use? The Torah explicitly stated: “Speak to the children of Israel, that they bring you a red heifer without defect, in which there is no blemish, and upon which never came a yoke” (Bamidbar 19:2). A red heifer is disqualified by a burden.
Abayye said: There, the baraita is referring to the case of a red heifer whose owner is leading it from city to city. When the animal is removed from its habitat, it requires additional security. In that case, tying the heifer with its reins is conventional rather than excessive security. Therefore, the bit is not considered a burden. Rava said: A red heifer, whose monetary value is high, is different and therefore secured more carefully than other cows. Ravina said: The baraita is referring to a red heifer that is rebellious and headstrong. Therefore, it requires added security.
There are many halakhot that relate to the Red Heifer, as detailed in tractate Para in the order of Teharot. Some of them deal with the precise definition of a yoke and the labors that disqualify a Red Heifer. All the explanations offered in this context are based on the assumption that all measures necessary for reasonable and essential security of a heifer, even if they would be considered a burden with regard to a different animal, are considered neither a burden nor a yoke.
Ultimately, the unique characteristics of the para aduma do not allow us to derive the laws of Shabbat from it.