Kesubos 2a: If the kallah became a niddah on the wedding day and they delayed the wedding, does the chosson have to start supporting the kallah?
Ran: It seems that this Gemara supports the Rambam’s opinion that chuppah means yichud; thus now that she is a niddah, they are forbidden to be alone together, and chuppah cannot take place. That’s why the Gemara considers the possibility that the chosson does not need to support her, since the delay is beyond his control. But according to those Rishonim who hold that chuppah just means that the kallah enters the chosson’s house or domain, why does the wedding need to be delayed? The other Rishonim respond that although the wedding does not need to be delayed, the Chachomim allowed the chosson to delay it because they cannot have relations.
כתובות ב ע”א: פירסה נדה, מהו?
ר”ן: איכא דיליף לה מהכא דחופה היינו יחוד ולפיכך כשפירסה נדה ולא בעל אסורה להתיחד כדאמרינן לקמן דהוא ישן בין האנשים ואשתו ישנה בין הנשים ולאו בת חופה היא ומשום הכי אינו מעלה לה מזונות… ואחרים אומרים דחופה לאו היינו יחוד אלא חופה היינו כל שהביאה הבעל מבית אביה לביתו לשם נשואין וכו’ וכי תימא פירסה נדה למה אינו מעלה לה מזונות הרי בידו להכניסה לחופה! היינו טעמא שכיון שאין חופה זו מסורה לביאה לא חייבוהו חכמים לכנסה.
Rav Avrohom Pam was once mesader kiddushin, and that night at 2 AM, the chosson called him up with a question. “I just realized that one of the witnesses for the yichud room was a relative. Is my wife permitted to me, or do we need to do the yichud over again with kosher witnesses?” Rav Pam told him it was okay, based on an Ohr Somayach. There is a disagreement between the Rambam and other Rishonim brought by the Ran if chuppah is yichud at all. And even if you need yichud, the Ohr Somayach (on Hilchos Ishus Perek 10) is not certain if the eidim are l’kiyumei milsa (necessary to make the chuppah take effect). Thus there is a sfek sfeika (double doubt) and it is permitted.
Rav Pam told this story to Rabbi Yisroel Reisman and then commented, “This halacha is also relevant for a chuppas niddah. At the wedding, they don’t do yichud because it’s not allowed. A few days later, when the wife goes to the mikveh, they do yichud. We are lenient, even lechatchilah, and don’t require two witnesses on this yichud. But if the chosson is a talmid chacham and asks me, then I recommend doing it with witnesses.”
Source: Rabbi Reisman, First tape on Yoreh Deah Siman 195, at 32 minutes
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