Zevachim 52B

ושאינו נשאר לא ימצה! תרי תנאי ואליבא דרבי ישמעאל.

And that which does not remain, i.e., if there is no blood remaining, he should not squeeze it out. This indicates that failure to squeeze the blood does not disqualify the offering. The Talmud answers: There are two tanna’im, and they disagree with regard to the opinion of R' Yishmael.

אמר רמי בר חמא, האי תנא סבר: שירים מעכבי. דתניא: ״הכהן המחטא אתה״⁠ – אותה שניתן דמה למעלה, ולא אותה שניתן דמה למטה.

The Talmud continues its discussion of the remainder of the blood. Rami bar Ḥama says: This following tanna holds that failure to pour the remainder of the blood of offerings whose blood is sprinkled inside the Sanctuary disqualifies the offering, as it is taught in a baraita: “The priest that sacrifices it for sin should eat it” (Leviticus 6:19). The verse states the word “it” to teach that it, the offering whose blood was sprinkled correctly, above the red line of the altar, is valid, and the priest may eat the meat. But this is not so for an offering whose blood was sprinkled below the red line, which is disqualified.

אמרת: וכי מאין באתה? מכלל שנאמר: ״ודם זבחיך ישפך על מזבח וגו׳״⁠ – למדנו לניתנין במתן ארבע, שאם נתנן במתנה אחת ⁠– כיפר. יכול אף הניתנין למעלה שנתנן למטה כיפר?

The baraita continues: You said this, but from where did you come? In other words, why would one think that such an offering is valid, so that the verse needs to teach that it is not? The baraita explains: From the fact that it is stated: “And you should offer your burnt offerings, the flesh and the blood, upon the altar of YHWH your God; and the blood of your offerings should be poured out against the altar of YHWH your God, and you should eat the flesh” (Deuteronomy 12:27), we learned that with regard to those offerings whose blood is placed with 4 placements on the corners of the altar, that if the priest placed them with only one placement, he has effected atonement. Therefore, since it is derived that if the priest does not present the blood on the specified corners of the altar, the offering is nevertheless valid, one might have thought that blood that should have been placed above the red line but that one placed below the red line effects atonement as well, and the offering is valid.