Which of two punishments can the court enforce? TB Ketubot 37

The principle kim lay mederabah menay (קם (קים) ליה מדרבה מיניה) has been the underlying basis for most of the Gemara’s discussions for a whole week. This principle states that when a person is convicted of committing a sin with two different punishments like death and payment, the court can only enforce the harsher punishment. Finally, today’s daf TB Ketubot 37 provides us with the scriptural basis for this principle. In fact, we need two different verses to cover all the different combinations of punishments.

“The mishna states that one liable to receive the death penalty is exempt from payment, as it is stated: “And yet no harm follow, he shall be punished, etc.” (Exodus 21:22). (Two men are exchanging blows and a pregnant woman comes between them. One of the blows lands on her and causes a miscarriage. Nevertheless, in this scenario she doesn’t die. The man who struck her has to pay monetary damages for the fetus. If she died because of the blow, the man is liable for the death penalty and exempt from paying the damage of the fetus. gg) The Gemara asks: And is this principle derived from here? Actually, it is derived from there: “And to be beaten (i.e. lashed-gg) before his face according to the measure of his iniquity” (Deuteronomy 25:2). From the term: His iniquity, it is inferred: You can hold one who performs one action liable for one iniquity, i.e., punishment for violating one prohibition, but you do not hold him liable for two iniquities, i.e., punishments for violating two prohibitions.

“The Gemara answers: One of these derivations, from the verse “And yet no harm follow” is stated with regard to one who performed an action for which he is liable to receive the death penalty and to pay money, and the liability to be executed exempts him from payment. And one of these derivations, from the verse “According to the measure of his iniquity,” is stated with regard to one who performed an action for which he is liable to receive lashes and to pay money, and he receives only one punishment. The Gemara elaborates: And both derivations are necessary, as if the Torah taught us this halakha only with regard to death and money, one would assert that the exemption from payment is due to the fact that there is loss of life, the ultimate punishment, leaving no room for additional punishment; however, in the case of lashes and money, where there is no loss of life, say no, there is no exemption and he is flogged and pays.

“And if the Torah taught us this halakha only with regard to lashes and money, one would assert that the exemption from payment is due to the fact that the prohibition that he violated is not severe, as it is punishable by lashes, and for violating a prohibition that is not severe one does not receive two punishments. However, with regard to death and money, where the prohibition that he violated is severe, say no, he is not exempt from receiving two punishments. Therefore, it was necessary for the Torah to teach both derivations.” (Sefaria.org translation)