QUESTION: The Gemara teaches that when a man tells a woman that he is giving money to her in order for her to become Mekudeshes to another man, the Kidushin takes effect. This is derived from the procedure of freeing an Eved Kena'ani.

The law is that Kidushin cannot be made without the consent of both parties. Why, then, can one man betroth a woman on behalf of another man without having been appointed as a Shali'ach by the other man to do so? RASHI (DH Heilach) explains that the Mekadesh indeed appointed his friend as his Shali'ach to marry the woman on his behalf by giving her a Perutah.

However, if he was appointed as a Shali'ach, the Kidushin obviously takes effect. Why does the Gemara need to derive from the Halachah of Eved Kena'ani that the Kidushin takes effect?

(a) RASHI explains that in an ordinary case of a man who appoints a Shali'ach to be Mekadesh a woman for him, the Shali'ach uses the money of the Meshale'ach, the man who appointed him. The Halachah of Eved Kena'ani teaches that he may use his own money to effect Kidushin for the Meshale'ach. This is the most straightforward way to explain the Gemara.

(b) The RITVA explains that the man who gave the money to the woman was not a Shali'ach. Rather, after he gave the Perutah for Kidushin, the other man (who wants to marry the woman) said to the woman, "I want you to become Mekudeshes to me with the Perutah that my friend gave to you." It is the Halachah of Eved Kena'ani which teaches that the Kidushin takes effect in such a case.

Why does the Ritva not explain like Rashi, that even if the man who gives the money was appointed as a Shali'ach, the Halachah of Eved Kena'ani is necessary to teach that the Shali'ach may give his own money?

Perhaps the Ritva understands that if the giver of the money was a Shali'ach, it is obvious that the Kidushin takes effect even when he gives his own money. Since he gives the money for the benefit of the one who appointed him, he is considered to have loaned that money to the Meshale'ach. The act of giving the money for Kidushin causes the money to become a loan to the Meshale'ach at the same moment the money becomes the property of the woman ("Ba'in k'Achas"). (Even if the man who gives the money does not expect the Meshale'ach to reimburse him, the money he gives is considered a loan which he forgives.) For this reason, the Ritva explains that the one who gives the money is not a Shali'ach and therefore cannot create a loan to the Meshale'ach by giving money to the woman (since the Meshale'ach did not request the loan).

Rashi, in contrast, maintains that when the Shali'ach gives his own money on behalf of the Meshale'ach, the money itself does not become the property of the Meshale'ach. Rather, the Meshale'ach merely owes him money because he incurred an expense at the request of the Meshale'ach. Therefore, a source is needed to teach that the Kidushin takes effect.

QUESTION: Rav Papa rules that if a woman gives a Perutah to a man and says, "Take this, and I will become Mekudeshes to you," she becomes Mekudeshes. Rav Ashi asks that "Nechasim she'Yesh Lahem Achrayus" (i.e. land, or "Karka") cannot be transferred "Agav" -- as a secondary acquisition -- by way of "Nechasim she'Ein Lahem Achrayus" (i.e. mobile property, or "Metaltelin"). Only Metaltelin can be acquired "Agav" Karka.

In what way is the woman considered "Nechasim she'Yesh Lahem Achrayus"? RASHI explains that the verse compares a person to Karka -- "v'Hisnachaltem Osam" (Vayikra 25:46) -- and thus a woman is considered "Nechasim she'Yesh Lahem Achrayus."

This verse, however, refers to Avadim Kena'anim. The Gemara later (22b) derives from this verse that one may acquire an Eved Kena'ani in the same manner that one acquires land -- with Kesef, Shtar, or Chazakah. No verse compares a free person, or even an Eved Ivri, to Karka. Indeed, the Gemara finds other sources from which it derives that one may acquire an Eved Ivri or a wife with Kesef and Shtar. Why does Rashi cite this verse as the source that a woman is considered "Nechasim she'Yesh Lahem Achrayus"? (TOSFOS DH Im Ken)

Moreover, if a woman is compared to Karka with regard to Kinyan Agav, does this mean that a man can acquire Metaltelin together with the woman through the Kinyan of Kidushin?

The RASHBA asks that even if a Kinyan Agav can be used to make a secondary Kinyan of Karka together with Metaltelin, why would one think that a woman can be acquired through Agav? Just as a Kinyan Chazakah cannot be used for Kidushin because there is no source for such a Kidushin in the Torah, a Kinyan Agav also should not be a valid form of Kidushin.

ANSWER: The RAMBAN and RASHBA explain that the Gemara does not intend to make a literal comparison between a woman and Karka, or to suggest that a Kinyan Agav should work for Kidushin. Rather, the Gemara means that even if a woman would be compared to Karka, and even if a woman could be acquired through Agav, it would not suffice to explain why giving a Perutah to a man can create Kidushin. (TOSFOS, DH Im Ken, gives a similar answer to the question of how Agav could effect a Kidushin.)