Talmud do Jewamot 9:6

MISHNAH: The levir does not cause her to eat heave⁸¹Since he cannot acquire his sister-in-law otherwise than by sexual relations, after which she will be his wife in all respects, a woman engaged to be married by the levir is not part of his clan.. If she spent six months for her husband and six months for the levir, or even all the time for the husband except for one day for the levir⁸²The moment a levir enters the picture, the earlier acquisition by the husband is suspended., or all the time for the levir except for one day for the husband, she cannot eat heave. That is the earlier Mishnah⁸³Both Mishnaiot 3 and 4.. The court in later times said that no woman eats heave unless she had been entering the bridal chamber⁸⁴The definitive marriage. For the original husband, no sexual act is required..

“If she spent six months for her husband and six months for the levir, she cannot eat heave. Not only six months for the levir but even all the time for the levir except for one day, she cannot eat heave.” The Mishna follows neither the earliest not the last Mishnah, but the intermediate development. As it was stated⁹¹A similar statement is in Tosephta 5:1, where, however, the intermediate Mishnah is not mentioned. Cf. also Terumot 8:1, Note 9.: First, they were saying that a preliminarily married woman, daughter of an Israel, could eat heave, for they were explaining: “If a Cohen acquires a person, acquistion by money⁹²Lev. 22:11. The verse ends: “He shall eat [the Cohen’s sacred food]”. A parallel statement in the Babli, 57b.;” for what would be the difference between one who acquires a wife and one who acquires a slave girl⁹³The slave girl, by becoming the property of a Jew, is presumed to become Jewish by immersion in a miqweh. Then she has to follow all Jewish laws valid for women (only that, being unable to marry, she is permitted guiltless unmarried sex with everybody except Jewish men). By manumission she would become a full Jewish woman. While a Gentile cannot become impure by biblical standards, the immersion in the ritual bath makes her subject to all rules of purity. If her owner is a Cohen, she may eat his sacred food if in the appropriate state of ritual purity.
A wife is usually acquired in preliminary marriage, as far as criminal law is concerned, by a gift of money or its equivalent. The argument is shaky since one should mention that if the wife is acquired by a matrimonial contract or by sexual relations without a gift of money (Mishnah Qiddušin 1:1), there would be no reason to permit heave to the Israel woman preliminarily married to a Cohen. Nowhere do we find that the way the preliminary marriage is effected makes any difference.? They changed, to say: after twelve months, when he becomes responsible for her upkeep. The court of the later ones said: A woman never eats heave before she enters the bridal chamber⁹⁴Tosephta 5:1. However, the same Tosephta (and the Yerushalmi. Yebamot 4:12, Note 197) mentions that in a famine, R. Tarphon (a Cohen) preliminarily married 300 women to give them access to sanctified food. This means that the “later Mishnah” has to be dated some time after the destruction of the Temple when, probably, the importance of heave for the income of Cohanim was rapidly diminishing.. ⁹⁵Tosephta 5:1.”Already Rebbi Joḥanan ben Bagbag sent to Rebbi Jehudah ben Bathyra⁹⁶The leader of Babylonian Jewry in the first half of the 2^nd Century C.E. at Nisibis: They say in your name that the preliminarily married daughter of an Israel eats heave. He sent back the following: I had been convinced that you are knowledgeable in the secrets of the Torah, but you do not even know the rules de minore ad majus! Since money can acquire a Gentile slave girl to permit her to eat heave, but she cannot be acquired by sexual relations⁹⁷Being Gentile, she could be married to a Gentile by sexual relations. But sexual relations with her are forbidden to a Jew and, therefore, she cannot be acquired by a Jew through sexual relations either as a slave or a wife. to permit her to eat heave, whereas a wife can be acquired by sexual relations to permit her to eat heave⁹⁸If preliminary and definitive marriage are enacted together in the bridal chamber without any gift of money, the woman is a wife and entitled to eat her husband’s food by biblical standards., it is only logical that money can acquire a wife to permit her to eat heave! But what can I do? They said that no woman eats heave before she enters the bridal chamber,” and they supported it by the verse⁹⁹Num. 18:11. The wife is part of the household only after the definitive marriage. The argument is rejected in Sifry Num. 117, since in. v. 13 a similar restriction is noted, “every pure person in your household shall eat it,” and it is a generally accepted hermeneutical principle that “two consecutive restrictions mean a relaxation”, in this case, that the wife may eat heave from the moment of the preliminary marriage. Therefore, the restriction to definitively married wives is purely rabbinical.: “Every pure person in your household shall eat it.” Rebbi Yudan said, that is an argument de minore ad majus that can be reversed! Because he could say to him, since a Gentile slave girl can be acquired by active possession¹⁰⁰The word חֲזָקָה “grasping” can have two very different meanings. In legal arguments, it denotes a general assumption which generates prima facie evidence. In the law of real estate and slaves, it denotes the exercise of possession. For example, if an intestate person dies without heirs (e. g., a proselyte who failed to start a Jewish family), his property becomes ownerless and is up for grabs. Therefore, if somebody goes to the ownerless real estate and acts as proprietor, fencing in or harvesting a field or painting a house, he has acquired the piece of real estate by his action. Similarly, if somebody takes an ownerless slave from the estate and tells him to work on his orders, the work of the slave makes him the property of the person giving the orders. The work can be quite symbolical, such as carrying a stone for a short stretch, to qualify as חֲזָקָה and if the acquirer is a Cohen, the slave is qualified to eat heave. Therefore, the means of acquisition of slave girls and wives are only partially comparable; the ways of acquisition of a slave are not subordinated to those for a wife. to permit her to eat heave, what can you say about a wife who cannot be acquired by active possession? If an argument de minore ad majus can be reversed, the argument is invalid.