Mekách táut / szimpon

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When an Israelite woman marries a priest, even a minor three years and one day old, she may partake of terumah and the breast and thigh [given the priests from the peace sacrifices].
According to Scriptural Law, she may partake of these foods from the time that she was consecrated. Our Sages, however, forbade her from partaking of them until she enters the chupah. [This is a] decree, [instituted] lest she give her father and brother terumah to eat while she is a consecrated woman in her father's home.

Ravina elaborates: And this is the question that he sent to him: I heard about you that you say that in practice the daughter of a non-priest betrothed to a priest may partake of teruma, and we are not concerned about an annulling factor [simfon], i.e., that he might find some blemish in her through which the betrothal would be considered retroactively invalid. If so, she would have eaten teruma when she was not permitted to do so. And it was with regard to this issue that Rabbi Yehuda ben Beteira sent to him: And do you not say this? I know about you that you are an expert in many areas of Torah; do you not know how to teachhalakhotbased on an a fortiori inference?

The Gemara asks: And ben Bag Bag, what does he say about this a fortiori inference? The Gemara answers that he maintains that this a fortiori inference is invalid because he does not accept that there can be a claim of simfon with regard to the acquisition of slaves. The reason is that if it is an exposed blemish that the master found on the slave, he saw the blemish and purchased him regardless. Therefore, he cannot later claim that the transaction was unfair. If it is due to hidden blemishes on his slave, what difference does that make to him? Why should it matter if a slave has hidden blemishes? He needs him only for labor, and he does not care if he has hidden blemishes that do not impair his ability to perform labor.

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