Yevamot

and the levirate bond of a married woman renders her 'doubtfully married'.  'The levirate bond of a betrothed woman renders her doubtfully betrothed', for were we to assume that she is regarded as definitely betrothed, [how could both] BETH SHAMMAI AND BETH HILLEL AGREE THAT SHE MAY SELL IT OR GIVE IT AWAY AND THAT HER ACT IS LEGALLY VALID when we learned: If she came into the possession of property while she was betrothed, Beth Shammai said, she may sell it, and Beth Hillel said, she may not sell it, but both agree that if she had sold or had given it away her act is legally valid!  Consequently  it must be inferred that the levirate bond of a betrothed woman renders her 'doubtfully betrothed'.  'The levirate bond of a married woman renders her doubtfully married', for had it been possible to assume that she is regarded as definitely married, [how could] Beth Shammai state that THE HEIRS OF HER HUSBAND ARE TO SHARE IT WITH THE HEIRS OF HER FATHER when we learned: If she came into the possession of property while she was married, both  agree that, if she had sold or given it away, her husband may seize it from the hand of the buyers!  Consequently it must be inferred that the levirate bond of a married woman renders her 'doubtfully married'. Said Rabbah to him:  Why, then, do they  dispute on [the question of the estate] itself after the death [of the widow]? Let them rather dispute on the question of the usufruct while she is alive! No, said Rabbah, both clauses deal with property which came into her possession while she was married; and the levirate bond of a married woman stamps her as doubtfully married. In the first clause, therefore, where she is alive, she is the certain possessor  while they are only doubtful possessors, and doubt cannot override a certainty.  In the final clause, however, where she is dead, both groups come equally as heirs  and are, therefore,  to take equal shares. Abaye pointed out an objection against him:  Cannot a doubt, in accordance with the view of Beth Shammai, override a certainty? Surely we learned: [In the case where] a  house collapsed upon a man  and his father or upon a man  and those whose heir he was,  and that man had against him the claim of his wife's kethubah  or that of a creditor,  [and in the first case], the heirs of the father plead that the son died first and the father afterwards,  while the creditor pleads that the father died first and the son afterwards,  Beth Shammai hold [that the amount in dispute is] to be divided,  and Beth Hillel hold that the estate is to remain in its former status.  Now here, surely, [the claim of] the heirs of the father is a certainty  and that of the creditor is only a doubt  and yet  the doubtful claim overrides the certainty!  — Beth Shammai are of the opinion that a bond of indebtedness which is due for repayment is regarded as [already] repaid! And whence do you derive this?  — [From] what we learned: If their husbands  died before they drank,  Beth Shammai rule that they are to receive their kethuboth  and that they need not drink,  and Beth Hillel rule that they either drink  or they do not receive their kethuboth.  [But how can it be ruled,] 'They either drink', when the All Merciful said, Then shall the man bring his wife  and he is not there! Consequently [the meaning must be that] as they do not drink they are not to receive their kethuboth.  Now here, surely, it is a matter of doubt, it being uncertain whether she did play the harlot  or not,  and yet the doubt overrides the certainty.  Consequently  it must be inferred that a bond of indebtedness which is due for repayment is regarded as already repaid. Abaye,  then,  should have raised his objection from this!  — [The law of] a wife's kethubah might be different owing to considerations of courtesy. Then let him  raise his objection from the law of the kethubah in our Mishnah!  They  do not dispute this point. But do they not? Surely we learned,  IF SHE DIED, WHAT SHALL BE DONE WITH HER KETHUBAH AND WITH PROPERTY THAT COMES IN AND GOES OUT WITH HER? BETH SHAMMAI SAID: THE HEIRS OF HER HUSBAND ARE TO SHARE IT WITH THE HEIRS OF HER FATHER; BETH HILLEL SAID: THE PROPERTY IS TO REMAIN WITH THOSE IN WHOSE POSSESSION IT IS! — It is this that was meant: IF SHE DIED, WHAT SHALL BE DONE WITH HER KETHUBAH? and then [the enquiry] was abandoned. As to PROPERTY THAT COMES IN AND GOES OUT WITH HER, BETH SHAMMAI SAID: THE HEIRS OF HER HUSBAND ARE TO SHARE WITH THE HEIRS OF HER FATHER AND BETH HILLEL SAID: THE PROPERTY IS TO REMAIN WITH THOSE IN WHOSE POSSESSION IT IS. Said R. Ashi: The inference from the expressions in our Mishnah leads to the same conclusion;  for it was stated, THE HEIRS OF HER HUSBAND ARE TO SHARE WITH THE HEIRS OF HER FATHER  and it was not stated 'the heirs of the father [are to share it] with the heirs of the husband'.  This proves it. [Reverting to the previous question,]  Abaye replied: The first clause [deals with property] that came into her possession while she was awaiting [the decision of] the levir,  and the latter clause [with such] as came into her possession while she was still with her husband.