Ze’eiri says: Permitted and forbidden substances combine with regard to the prohibition against offering leaven on the altar, as well, as it states: “For any [kol] leaven and any [kol] honey should not be offered as a burnt-offering before YHWH” (Leviticus 2:11). This indicates that one is also liable for sacrificing leaven in a mixture in addition to the liability for sacrificing pure leaven. The Talmud asks: In accordance with whose opinion did Ze’eiri issue his ruling? It is in accordance with the opinion of R' Eliezer, who derives from the term kol in the verse “You should eat nothing [kol] leavened” (Exodus 12:20) that a mixture with part leaven is forbidden on Passover.
אי הכי לענין חמץ נמי! אין הכי נמי. אלא לאפוקי מאביי דאמר: יש הקטרה בפחות מכזית, קא משמע לן: אין הקטרה בפחות מכזית.
The Talmud raises a difficulty: If so, then with regard to the matter of leavened bread on Passover, one should also be liable for eating leaven combined with a permitted substance, e.g., less than an olive-bulk of bread soaked in wine, so that the volume is now an olive-bulk. The Talmud answers: Yes, indeed it is so. Rather, when Ze’eiri specifies that the prohibition applies with regard to sacrificing leaven in offerings, he meant to exclude the statement of Abaye, who says: There is significance to sacrificing less than an olive-bulk of leaven on the altar, i.e., one is flogged for sacrificing an offering of that kind. By noting that one is liable due to the fact that permitted substances combine with forbidden substances, Ze’eiri teaches us that there is no significance to sacrificing less than an olive-bulk, and therefore this is not punishable by lashes.