Ketubot 31A

וקרע שיראין של חבירו.

and at the same time he tore another’s silk [shira’in]. The question is whether the liability to receive the death penalty exempts him from the liability for payment incurred at precisely the same moment.

גופא, אמר רב חסדא: מודה רבי נחוניא בן הקנה בגונב חלבו של חבירו ואכלו שהוא חייב, שכבר נתחייב בגנבה קודם שיבא לידי איסור חלב. לימא פליגא דרבי אבין. דאמר רבי אבין: הזורק חץ מתחילת ארבע לסוף ארבע, וקרע שיראין בהליכתו ⁠— פטור. שעקירה צורך הנחה היא. הכא נמי: הגבהה צורך אכילה היא!

§ The Talmud analyzes the matter itself. Rav Ḥisda said: R' Neḥunya ben HaKana concedes in the case of one who steals another’s forbidden fat and eats it that he is obligated to pay for the fat, as he is already liable for theft before he comes to violate the prohibition against eating forbidden fat. The Talmud comments: Let us say that Rav Ḥisda disagrees with R' Avin, as R' Avin said: One who shoots an arrow from the beginning of 4 cubits to the end of 4 cubits in the public domain on Shabbat, thereby performing a prohibited labor for which he is liable to receive a court-imposed death penalty, and the arrow ripped silk as it proceeds, is exempt from the obligation to pay for the silk because he is liable for the more severe punishment for desecrating Shabbat. Although the silk was ripped prior to completion of the prohibited labor, as the arrow had not yet come to rest, he is nevertheless exempt, as lifting is a prerequisite for placement. The prohibited labor of carrying on Shabbat is comprised of lifting of the object and placement. Once he shot the arrow, its movement through the air is a continuation of his act of Shabbat desecration, for which he is liable to be executed. Here, too, say that lifting the fat is a prerequisite for eating, and therefore he should be exempt from payment.