Resources for Nedarim 30
The גמרא says that according to בר פּדא who says you can make something הקדש for an infinite amount of time such that even after פּדייה be automatically become הקדש again, it should follow that if you give a woman two פּרוטות and try to be מקדש her now as well as after you divorce her that both קידושין’s should be valid. The גמרא is דוחה that this is more similar to a case of where someone else is פּודה the הקדש where the הקדש done beforehand will not be valid. The גמרא does not seem to have a מסקנא to the question as to whether she is מקדושת or not. The ר"ן brings the רשב"א who says that we are פּושט the question from a גמרא in כתובות that says that if a person says “this field I will sell you should be הקדש when I buy it back”, the field will become הקדש at that time. This proves that by our case of the two פּרוטות the קידושין שניים will work. The רשב"א seems to have understood that the issue of our גמרא was based on the fact that there will be a time when the person has no authority to make the הקדש and it therefore may impede his ability to make the הקדש. After all, we know that if a person gives a married woman a פּרוטה and says, “you are married to me as soon as you get divorced” that it does not work because its not בידו. If so, we have the same issue here since there will come a time that its not בידו before the קידושין is חל. The רשב"א therefore proves from the גמרא in כתובות that allows someone to say “my land that I will sell you shortly is הקדש when I buy it back” that clearly that not owning it the whole time is not an issue. The ר"ן disagrees and says there is no proof from that גמרא since when he says “my land that I will sell you should be הקדש after I buy it back” he has the ability at the present time to be מקדיש it. However, when using two פּרוטות to be מקדש her now and later, she is becoming an אשת איש right now and you cant give קידושין to an אשת איש. The ר"ן seems to have understood that the issue of our גמרא is not the fact that it won’t be in his power to be מקדש her later but rather that she is an אשת איש now. The אבני מילואים in סימן מ"ג אות י"א says a fascinating נפקא מינה: what if a man gives a פּנויה one פּרוטה and says you are מקודשת to me only after you marry and get divorced from someone else? He says that according to the רשב"א it may not work but according to the ר"ן it certainly works and she is מקודשת! The אבני מילואיםsays that is actually the פּשטות since why else would the question have been with two פּרוטות instead of one. What is unclear to me is that the case of בר פּדא where he is מקדש it for now and after he is פּודה it himself is a case that all agree works, so you should see that being מקדש for now and later works. Unless you answer that being מקדש and being פּודה it myself is like it never left my רשות and therefore the issue of being מקדש something מקודש is somehow not an issue.
The ר"ן famously asks why is it that when a woman is divorced we view it as פּדאום אחרים--why don’t we say it is like she was originally מקנה herself and now is קונה herself back? He answers that a woman is not מקנה herself to the man but is simply removing her ability to stop the קנין and makes herself like הפקר for the man to be קונה. Theאבני מילואים in סימן מ"ג אות ב says that this explains the following question: we know a child can be קונה via דעת אחרת מקנה even מדאורייתא according to some. If so, why don’t we say that a child can be מקדש a grown woman מדאורייתא because of דעת אחרת מקנה? He answers that according to the ר"ן there is no question since the lady isn’t מקנה herself to the husband at all. Rather, she just makes herself like a דבר של הפקר.
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