Nazir 38A

דלית ליה צירוף, ״מכל אשר יעשה״, מאי דריש ביה? אמר לך: ההוא מיבעי ליה: לעולם אינו נזיר עד שיזיר מכולן.

who is not of the opinion that the principle of combination is operative, as he renders one liable for consumption of forbidden substances of any amount (see Makkot 13a), what does he derive from the verse “anything that is made of the grapevine” (Numbers 6:4)? The Talmud answers: R' Shimon could have said to you: That verse is necessary to teach that one is never considered a nazirite until he vows naziriteship from all of them. R' Shimon maintains that if one vows to be a nazirite only with regard to one or two of the prohibitions of naziriteship, the vow does not take effect at all.

אמר רבי אבהו אמר רבי אלעזר: כל רביעיות שבתורה, אין היתר מצטרף לאיסור, חוץ מרביעית שבנזיר, שהרי אמרה תורה ״משרת״. מאי איכא בין רבי יוחנן לרבי אלעזר?

R' Abbahu said that R' Elazar said: With regard to every halakha that is in the Torah that involves 1/4th-log, a permitted substance does not combine with a forbidden substance to complete this measure, apart from the quarter-log of a nazirite. In the case of a nazirite, permitted liquid combines with wine to render him liable, as the Torah stated: “Soaked” (Numbers 6:3). The Talmud asks: What difference is there between the opinion of R' Yoḥanan, who stated (35b) that a permitted substance does not combine with a forbidden one with regard to any prohibition of the Torah apart from that of a nazirite, and that of R' Elazar, who apparently says the same thing in different terms?

איכא בינייהו, דרבי יוחנן מרבי אפילו אוכלין, ורבי אלעזר, משקין ⁠— אין, מידי אחרינא ⁠— לא.

The Talmud answers: There is a difference between them, as R' Yoḥanan amplifies the halakha to include even foods, i.e., he renders a nazirite liable for eating an olive-bulk of bread and grapes combined, and R' Elazar maintains that with regard to liquids, yes, the permitted combines with the forbidden, but for other matters, i.e., solids, no, the different foods do not combine.