What’s the definition of a real gift? TB Nedarim 48

Today we learn about the story of Beit Ḥoron where we learn what type of subterfuge is invalid to get around a vow. “An incident occurred involving someone in the city of Beit Ḥoron whose father had vowed not to derive benefit from him, and the son was marrying off his own son and wanted his father to be able to participate in the wedding meal. And he therefore said to another: The courtyard where the wedding will take place and the wedding meal are given before you as a gift, but only so that my father will come and eat with us at the meal. The recipient said: If they are mine, they are all hereby consecrated to Heaven, i.e., the Temple, and are forbidden to everyone. The son said to him in anger: And did I give you my property so that you should consecrate it to Heaven? He, the recipient, said to him: You gave me your property only so that you and your father would eat and drink and thereby appease each other, and the sin of transgressing the vow would be hung on his, i.e., my, head, as I enabled the transgression. The Sages therefore said: Any gift that is not so absolute so that if the recipient were to consecrate the gift it would be consecrated, is not a gift. In other words, in order for it to be a gift, the recipient must have the ability to consecrate it.” (Sefaria.org translation) Clearly the father of the groom only “gave” the hall and the meal to his friend only so his father could attend. It wasn’t a true gift since the recipient can do whatever he wanted with it.

According to our daf TB Nedarim 48 the definition of a gift is simple. If the recipient of the gift can’t do whatever he wants with it like consecrated to the Temple, it is not a real gift. The Ran ד"ה כׇּל מַתָּנָה שֶׁאֵינָהּ שֶׁאִם הִקְדִּישָׁהּ תְּהֵא מְקוּדֶּשֶׁת אֵינָהּ מַתָּנָה raises a real interesting question. The Gemara daf TB Baba Batra 137b teaches that a gift given on the condition that it is returned (מַתָּנָה עַל מְנָת שֶׁתַּחְזִירֵהוּ) is a real gift. The example given there concerns the lulav and etrog. On the first day of Sukkot one has to own the lulav and etrog in order to fulfill the mitzvah. One is allowed to gift his lulav and etrog to somebody else in order that the person may recite the appropriate blessings with the expectation that the person returns the lulav and etrog in the same condition he received it. If the borrower does not return it, he has not fulfilled the condition. If he has not fulfilled the condition, the lulav and etrog retroactively do not belong to him. If the lulav and etrog do not belong to him, he has not fulfilled the mitzvah. From this Gemara we see that a gift is a gift even when the one who receives it cannot do whatever he wants with it.

The Ran solves this contradiction between our Gemara and the Gemara in TB Baba Batra by describing a qualitative difference between the two cases. In our Gemara the father of the groom really doesn’t give away anything. It is just a subterfuge to get his father to attend his grandsons wedding. In the case of the lulav and etrog, the owner wholeheartedly gives them to his fellow parishioner for the period of time it takes to say the blessings and wave the lulav and etrog in the six directions.