Kiddushin 8a: The Machlokes Rambam and Raavad on Obligation and Reliance in Kiddushin (Part 2)

Rabbi Zweig continues the analysis begun in yesterday's shiur, focusing on a Machlokes between the Rambam (רמב"ם) and the Raavad in Hilchos Mechirah, Perek 6, Halachos 1-2. The case involves a sale of 100 apples for $100. The Rambam rules that if 99 or 101 apples are delivered, the seller must provide the missing one or the buyer must return the extra—there is no din of onaah (price fraud) because the discrepancy is in quantity, not value. The mekach (transaction) is valid and requires correction. The Raavad disagrees: the mekach is battul (void) unless corrected, and he states this is learned from kiddushin: "davar zeh nigmar mi'kiddushin." The shiur investigates what in the Gemara (גמרא)'s sugya the Raavad is citing. The Gemara discusses a man who is mekadesh a woman "with a maneh" but only gives her a dinar (a small amount). The Gemara seems to say that if he doesn't give the full maneh, the kiddushin is battul. Yet the Raavad's case involves an obligation to make up the shortfall—in a sale, the seller owes the buyer the missing apple. How does the Raavad's rayah from kiddushin work if in kiddushin there is no debt obligation? Rabbi Zweig proposes that the Raavad must be learning the sugya such that the man does owe the woman the additional 99 (or the remaining value of the maneh). This is the key insight from yesterday's shiur: the case is not a pure tanai (condition) in which the man simply won't marry unless he gives the full amount. Rather, the man has obligated himself (mechuyav) to give the maneh. If he doesn't fulfill this obligation, the woman is in an impossible position—she relied on (somechas daatah) his commitment. Because he owes it, she can waive (be mechayel) the debt, and therefore she "owns" him—her mechilah validates the kiddushin.