Zevachim 159
הניתנין במתנה אחת שנתערבו בניתנין במתנה אחת ינתנו במתנה אחת (מהן) מתן ארבע במתן ארבע ינתנו במתן ארבע
<br> [IF BLOOD] WHICH REQUIRES ONE APPLICATION [WAS MIXED] WITH BLOOD [ALSO] REQUIRING ONE APPLICATION, IT [THE MIXTURE] SHOULD BE PRESENTED WITH ONE APPLICATION. [IF BLOOD] WHICH REQUIRES FOUR APPLICATIONS [WAS MIXED] WITH BLOOD REQUIRING FOUR APPLICATIONS, THEY MUST BE PRESENTED WITH FOUR APPLICATIONS. [BLOOD] WHICH REQUIRES FOUR APPLICATIONS WITH THAT WHICH REQUIRES ONE APPLICATION, R. ELIEZER SAID: IT [THE MIXTURE] MUST BE PRESENTED WITH FOUR APPLICATIONS. R. JOSHUA MAINTAINED: IT MUST BE PRESENTED WITH ONE APPLICATION. SAID R. ELIEZER TO HIM: BUT LO, HE TRANSGRESSES THE [INJUNCTION] NOT TO DIMINISH [FROM GOD'S COMMANDMENT]! LO, HE TRANSGRESSES THE INJUNCTION NOT TO ADD [THERETO], R. JOSHUA COUNTERED. THE INJUNCTION NOT TO ADD APPLIES ONLY WHERE IT IS BY ITSELF, REPLIED R. ELIEZER. THE INJUNCTION NOT TO DIMINISH APPLIES ONLY WHERE IT IS BY ITSELF, R. JOSHUA ANSWERED. MOREOVER, SAID R. JOSHUA, WHEN YOU MAKE [FOUR] APPLICATIONS YOU TRANSGRESS THE INJUNCTION NOT TO ADD, AND COMMIT A POSITIVE ACTION WITH YOUR OWN HANDS; WHEREAS WHEN YOU DO NOT MAKE [FOUR] APPLICATIONS YOU TRANSGRESS THE INJUNCTION NOT TO DIMINISH, BUT DO NOT COMMIT A POSITIVE ACTION WITH YOUR OWN HANDS.
מתן ארבע במתנה אחת ר"א אומר ינתנו במתן ארבע ר' יהושע אומר ינתנו במתנה אחת
GEMARA. R. Eleazar said: R. Eliezer declared them fit only in twos, but not singly. R. Dimi raised an objection: BUT THE SAGES MAINTAIN: EVEN IF THEY OFFERED ALL OF THEM SAVE ONE, IT MUST BE POURED OUT INTO THE DUCT. Said R. Jacob to R. Jeremiah b. Tahlifa: I will explain it to you: What does ONE mean? One pair.
אמר לו רבי אליעזר הרי הוא עובר על בל תגרע אמר ליה רבי יהושע הרי הוא עובר על בל תוסיף
Now, both are necessary. For if it were stated in the former case, I would argue that only there does R. Eliezer rule thus, because his atonement was already made therewith, but in the present instance he agrees with the Rabbis. While if it were stated in the present case, I would argue that only here do the Rabbis rule thus, but in the former instance they agree with R. Eliezer. Hence both are necessary.
א"ל רבי אליעזר לא נאמר בל תוסיף אלא כשהוא בעצמו א"ל ר' יהושע לא נאמר בל תגרע אלא כשהוא בעצמו ועוד א"ר יהושע כשנתת עברת על בל תוסיף ועשית מעשה בידך כשלא נתת עברת על בל תגרע ולא עשית מעשה בידך:
We learnt elsewhere: In the case of a flask into which a little water fell, R. Eliezer said: He [the priest] makes two sprinklings; but the Sages disqualify [it]. As for the Rabbis, it is well: They hold that we assume even distribution, and sprinkling requires a [minimum] standard, and sprinklings do not combine. But what does R. Eliezer hold? If he holds that there is no even distribution, what if he does sprinkle twice; perhaps he sprinkles [ordinary] water both times? - Rather, he holds that there is even distribution. Now, if he holds that sprinkling does not require a [minimum] standard, why must he sprinkle twice? - Rather, he holds that sprinkling does require a [minimum] standard. And if he holds that sprinklings do not combine, what if he does sprinkle twice? And even if sprinklings do combine, who can say that the standard is made up? - Said Resh Lakish: In truth he holds that there is even distribution, and sprinkling does require a [minimum] standard; but the case we discuss here is where one [standard quantity] was mixed up with another. Raba said: In truth there is even distribution, and sprinkling does not require a standard; but the Rabbis penalised [him] so that he should not benefit thereby. R. Ashi said: There is no even distribution, [therefore] he must sprinkle twice. <br>
<big><strong>גמ׳</strong></big> א"ר אלעזר לא הכשיר ר"א אלא שנים שנים אבל אחד אחד לא
An objection is raised: Rabbi said: According to R. Eliezer, the sprinkling of any quantity purifies, sprinkling does not require a standard, sprinkling [is permissible if] half [the water] is fit and half is unfit. <br>
אלא רבי אליעזר מאי קסבר אי קסבר אין בילה כי מזה שתי הזאות מאי הוי דילמא תרוייהו מיא קא מזי אלא קא סבר יש בילה אי קסבר אין הזאה צריכה שיעור למה לי שתי הזאות אלא קסבר הזאה צריכה שיעור ואי קסבר אין מצטרפין להזאות כי מזה שתי הזאות מאי הוי ואי נמי מצטרפין להזאות מי יימר דמלא ליה שיעורא