According to the Mishnah, if the kemitzah – taking a fistful from the meal-offering for placement on the altar – was done by the kohen with his left hand, the sacrifice is invalid. In the Gemara on today’s daf (=page) Rava presents the source for this law. Regarding the laws of a metzorah – someone suffering from biblical leprosy – who recovers from his condition and brings various sacrifices, we find that the blood of the sacrifice as well as the oil brought together with the sacrifice is to be placed by the kohen on the body of the recovered metzorah on three specific places – on his right ear, the thumb of his right hand and the big toe on his right foot (see Sefer Vayikra Chapter 14, and, in particular, pesukim or verses 14, 17, 25, 28). The repetition of these requirements leads Rava to conclude that the Torah is emphasizing that there are other laws in the Torah that are to be modeled after these actions and they must be done in a similar fashion. They are:
Defining “hand” as the right hand specifically teaches us the law regarding kemitzah.
Defining “foot” as the right foot specifically teaches us the law regarding halitzah.
Defining “ear” as the right ear specifically teaches us the law regarding a Hebrew slave who chooses to remain with his master.
Aside from the law of kemitzah, which is the meal-offering service in the Temple that we have been discussing, the other two cases relate to two different mitzvot. The halitzah ceremony is performed when a man who is married but did not have children passes away. According to Torah law, ideally the wife of the deceased should remain in his family by means of yibum – levirate marriage – to his brother. In the event that either of them does not want to carry through with yibum, halitzah can sever the relationship and allow her to marry anyone who she chooses. The Torah described the halitzah ceremony as one that demeans the brother who is not willing to take on the responsibility of building up his dead brother’s family, and it involves having the widow remove a shoe from his foot and spit before him (see Devarim 25:9).
According to the Torah if a Hebrew slave who has completed his obligation to his master chooses to remain with him, his ear is pierced to symbolize his servitude (see Shemot 21:6). Again, we learn that this is done to the right ear from the laws of the metzorah.