Arachin, Chapter 8, Mishnah 5. This chapter has been dealing with the laws of cheirem, property that a person dedicates with a declaration of "cheirem," which places it in the hands of the kohanim. Our mishnah asks a basic question about who and what can be dedicated in this way: does a person have the power to declare cheirem on anything that is under his control, or only on what is truly and completely his?
Dedicating What Is Not Fully Yours
The mishnah begins: "Hamachrim bino uvito, avdo veshifchato ha'ivrim, usdei miknato, einan muchramim." If a man pronounces the word cheirem over a child of his, over a Hebrew slave or Hebrew maidservant of his, or over a field that came into his hands through purchase rather than as his ancestral inheritance, his words are empty. Not one of these items enters the status of cheirem.
The mishnah supplies the principle behind this ruling: no one may place under cheirem "davar she'eino shelo," an object that does not belong to him. And the measure of true ownership here is whether he is able to sell the item. Yes, a father holds certain rights in his children, and a master holds certain rights in his Hebrew slave and maidservant, yet holding rights is not the same as owning. Since he has no power to sell any of them, they do not qualify as his possessions for the purposes of cheirem.
The purchased field works the same way. A field that a person bought is not permanently his, because at the yovel it returns to the ancestral owner from whom it was acquired. Since his hold on it is temporary, it is not fully his, and a declaration of cheirem upon it simply does not take effect.
Kohanim and Levi'im
The mishnah goes on: "Kohanim ulvi'im einan machrimim." Members of these two families lack the power to place what they own into cheirem. The source is the pasuk describing their fields, which the Torah calls "achuzat olam hu lahem," a possession that is theirs forever. From the case of their fields we extend the ruling to everything else in their hands: if their land is immune to cheirem, so is the rest of what they own.
Rabbi Shimon's Distinction
"Rabbi Shimon omer: haKohanim einan machrimin shehacharamim shelahem." Rabbi Shimon offers a different reason, and it applies to kohanim alone. A kohen cannot declare cheirem, because the cheirem property belongs to the kohanim in the first place. The one who makes the declaration chooses which kohen receives the item, so if a kohen dedicates his own property, he can direct it right back to himself. Nothing has changed hands, nothing has been accomplished, and the cheirem therefore does not take effect.
"HaLevi'im machrimim, she'einan hacharamim shelahem." Levi'im, by contrast, can declare cheirem, precisely because cheirem property is not theirs. It goes to the kohanim. When a levi dedicates something of his, the declaration achieves something real: the property is transferred out of his hands and into the hands of the kohanim.
Rebbi Rules Between Them
Rebbi now weighs the two views. In his judgment, when the subject is land, the opening opinion of the mishnah, that of Rabbi Yehuda, carries the day, and Rabbi Shimon would concede the point: no kohen and no levi may place a field of his into cheirem. "Shene'emar ki achuzat olam hu lahem," the verse defines their portion as theirs for all time. A field consecrated as cheirem never comes back to the one who owned it, not even when yovel arrives. Since the Torah guarantees that their holding stays with them permanently, such a field cannot be brought into cheirem in the first place.
"Vedivrei Rabbi Shimon bemetaltelin." Where movable goods are concerned, Rabbi Shimon's reasoning is the one that applies, since regarding such items the Torah never promised that they would stay forever in the possession of these families. A kohen or levi may sell his movable property, and what he may sell he may also dedicate as cheirem. At that point Rabbi Shimon's distinction takes over: a levi's declaration works, because cheirem goes to the kohanim and not to him, so the object genuinely leaves his hands; a kohen's declaration does not, since whatever he dedicates he can steer straight back to himself.