Yevamot

Now, if it could be assumed that a ma'amar, according to Beth Shammai, constitutes a perfect kinyan, let the one levir address a ma'amar  and constitute thereby a kinyan,  and let the other also address a ma amar  and thereby constitute a kinyan.  What then! [Is it your inference that] it  keeps the rival completely out?  Let then one levir address a ma'amar  and keep her out  and let the other levir also address a ma'amar  and keep her out!  What, however, may be said in reply? That a permitted ma'amar  does keep the rival out, while a forbidden ma'amar  does not keep her out; so also here, even according to him who maintains that a ma'amar constitutes a perfect kinyan, only a permitted ma'amar  constitutes a kinyan. but a forbidden one  does not. R. Ashi taught it  in the following manner: R. Eleazar said: It must not be assumed that a ma'amar, according to Beth Shammai, keeps the rival  completely out, and that she does not require even halizah; but rather it  keeps her out  and still leaves [a partial bond].  Said R. Abin: We also have learned the same thing: Beth Shammai said, 'they may retain them',  which implies that they may only retain them  but [that they may] not [marry them] at the outset.  Now, if it could have been assumed that a ma amar, according to Beth Shammai, keeps a rival out completely. let the one levir address a ma'amar,  and thus keep her out.  and let the other also address a ma'amar  and so keep her out.  But. surely. it was taught. BETH SHAMMAI SAY: HIS WIFE [REMAINS] WITH HIM WHILE THE OTHER IS EXEMPT AS HIS WIFE'S SISTER!  — The fact is, a yebamah who is eligible for all  is also eligible for a part;  a yebamah who is not eligible for all  is not eligible for a part. Rabbah inquired: Does a ma'amar, according to Beth Shammai, constitute marriage or betrothal? — Said Abaye to him: On what practical issue [does this question bear]? Shall I say on [the issue] of inheriting from her,  defiling himself to her  or annulling her vows?  Surely, [it could be answered that] seeing that in the case of  ordinary betrothal  R. Hiyya taught, that where the wife has only been betrothed  [the husband] is neither subject to the laws of onan  nor may he defile himself for her.  and she in his case is likewise not subject to the laws of onan  nor may she defile herself for him,  and that if she dies he does not inherit from her though if he dies she collects her kethubah;  is there any need [to speak of the case where] a ma'amar had been addressed!  Rather. [the question is] in respect of introduction into the bridal canopy: Does it  constitute a marriage and, therefore. no introduction into the bridal canopy is required.  Or does it perhaps constitute betrothal and, consequently, introduction into the bridal canopy is required? The other replied: If where he did not address to her any ma'amar it is written [in Scripture]. Her husband's brother shall go in unto her,  even against her will, is there any need [to speak of the case where] he has addressed to her a ma'amar!  The former retorted: Yes;  since I maintain that whenever a levir has addressed a ma'amar to his sister-in-law, the levirate bond disappears and she comes under the bond of betrothal. What [then is the decision]? — Come and hear: In the case of a widow awaiting the decision of the levir.  whether there be one levir or two levirs, R. Eliezer said, he  may annul [her vows]. R. Joshua said: [Only where she is waiting] for one and not for two.  R. Akiba said: Neither when she [is waiting] for one nor for two.  Now we pondered thereon: One can well understand R. Akiba, since he may hold that no levirate bond exists even in the case of one;  according to R. Joshua, the levirate bond may exist where there is one levir but not where there are two levirs.  According to R. Eliezer, however, granted that a levirate bond exists, one can understand why, in the case of one, he may annul, but why also in the case of two?  And R. Ammi  replied: Here it is a case where he addressed to her a ma'amar, and the statement represents the opinion of Beth Shammai who maintain that a ma'amar constitutes a perfect kinyan.  Now, if it be granted that it  constitutes a marriage, it is quite intelligible why he may annul her vows. If. however, it be assumed that it constitutes only a betrothal, how could he annul her vows? Surely we learned: The vows of a betrothed girl may be annulled by her father in conjunction with her husband!  -Said R. Nahman b. Isaac: What is meant by annulment? Jointly. According to R. Eleazar, however, who holds that a ma'amar, In the opinion of Beth Shammai, constitutes a kinyan only so far as to keep out the rival, how  could the annulment be effected even jointly?  — R. Eleazar can answer you: When I said that it  constitutes a kinyan so far only as to keep out the rival, [I meant to indicate] that a letter of divorce was not sufficient  but that halizah also was required;  did I say anything. however, as regards the annulment of vows! And if you prefer I might say. R. Eleazar can answer you: Is it satisfactorily explained according to R. Nahman b. Isaac?  Surely it was not stated 'they may annul' but 'he may annul'!  Consequently this must be a case where he  appeared before a court  and  a specified sum for alimony was decreed for her out of his estate; and [this is to be understood] In accordance with the statement R. Phinehas made in the name of Raba. For R. Phinehas stated in the name of Raba: Any woman that utters a vow does so on condition that her husband will approve of it.