Rabbi Yochanan and Reish Lakish debate whether a Pesach offering or a sin offering becomes disqualified if it is slaughtered with the intent to sprinkle its blood for the sake of a different sacrifice. Their disagreement centers on whether the laws of lishma (proper intent) can be derived from the laws of pigul (disqualifying intent regarding timing), which would imply that a thought during one sacrificial action about a different action could invalidate the offering.

A parallel debate arises regarding idol worship: if one slaughters an animal with the intent to offer its blood to an idol later, does that render the animal prohibited for benefit? The question is raised why both cases need to be stated—why not derive one from the other? This leads to a deeper exploration of the distinctions between them.

Rav Dimi reports that Rav Yirmia brought a proof supporting Rabbi Yochanan's view, while Rabbi Ilai supported Reish Lakish. Rav Yirmia's proof is based on a kal va'chomer, which undergoes two revisions after difficulties are raised. Rav Papa challenges Rabbi Ilai's proof, but the challenge is ultimately resolved.

In the Mishna, Rabbi Eliezer adds the case of a guilt offering that is disqualified if brought not lishma—with intent for a different sacrifice. A braita presents a dialogue in which Rabbi Yehoshua repeatedly rejects Rabbi Eliezer's proposed reasons. After three attempts, Rabbi Eliezer finally offers an explanation that holds. The Gemara then revisits various lines in the braita for further analysis.