Yoma 81A

שכוסס שעורים של תרומה ⁠— משלם את הקרן ואינו משלם את החומש. ״כי יאכל״⁠ — פרט למזיק.

who chews on barley of teruma that has not been ground or baked pays the principal and not an extra fifth. The reason is that it states “eats” (Leviticus 22:14), which excludes one who harms himself. Consuming raw barley is considered self-harm, not eating.

אמר רב שיזבי אמר רבי יוחנן: זר שבלע שזפין של תרומה והקיאן ואכלן אחר, ראשון ⁠— משלם (את) קרן וחומש. שני ⁠— אין משלם אלא דמי עצים לראשון בלבד.

Rav Sheizvi said that R' Yoḥanan said: In the case of a non-priest who swallowed plums of teruma whole and vomited them out, whereupon another person ate them, the first one pays the principal plus a fifth. When the first one benefited from the plums, he acquired them and must therefore pay for them, and the second one must pay their worth to the first one. Since they are only fit for fuel after the first one vomited them out, the second person is considered to have damaged their value as fuel. Therefore, he pays only the price of wood, i.e., fuel, to the first person.

האוכל והשותה אין מצטרפין. מאן תנא? אמר רב חסדא: במחלוקת שנויה, ורבי יהושע היא. דתנן, כלל אמר רבי יהושע: כל שטומאתו ושיעורו שוה ⁠— מצטרף.

§ It was taught in the Mishnah that food and drink do not combine. The Talmud asks: Who is the tanna who taught this? Rav Ḥisda said: This halakha is taught as a dispute, and the Mishnah is in accordance with the opinion of R' Yehoshua. As we learned in a Mishnah: R' Yehoshua stated a general principle: Any item that is identical to another item in its type of ritual impurity, e.g., impurity that lasts only until evening, and its measure for impurity, e.g., an olive-bulk, combines with the other item to reach one measure to render other items impure. Therefore, two half olive-bulk pieces of two corpses or of two animal carcasses, or two half lentil-bulk pieces from two creeping animals all combine to render other items impure.