Chullin 109: Yalta's Observations on Equivalency in Laws

A new Mishna teaches that to prepare the udder for eating, it must be opened to remove the milk.  Rav Yehuda teaches in the Gemara that the udder should be cut crosswise and pressed against the wall.  The Gemara continues by teaching about Yalta, part of the Exilarch's family and wife of Rav Nachman, was said to be learned and a participant in the rabbis' discussions.

We are told that Yalta observed that everything that G-d forbids us in law is permitted to us in an equivalent situation:

• blood is forbidden; liver is permitted
• intercourse during menstruation is forbidden; blood of purification is permitted
• we cannot eat the fat of cattle but we may eat the fat of wild beasts
• we may not eat swine's flesh but we may eat the brain of the shibuta fish
• married women are forbidden but divorcees are permitted while their husbands are alive
• the brother's wife is forbidden but levirate marriage is permitted
• the non-Jewess is forbidden but women are permitted when taken in war

Yalta then asks, "I wish to eat flesh in milk; where is the equivalent?"  Rav Nachman asked the butchers to prepare roasted, not cooked, udders for her.  He argued that the requirement to cit the udder crosswise and press it against the wall was only required when the udder was to be cooked but not roasted.

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