Commentary for Leviticus 4:18

יסוד מזבח העלה אשר פתח אהל מועד [AND HE SHALL POUR OUT ALL THE BLOOD AT] THE BASE OF THE ALTAR OF THE BURNT-OFFERING WHICH IS AT THE ENTRANCE OF THE APPOINTED TENT — this is the base on the west side, for it was that which was opposite to the entrance of the tent (cf. Zevachim 51a).

Opposite the entrance. Otherwise, why does it say “at the entrance of the Tent of Meeting.” You might ask: Why did Rashi not explain this above (v. 7) regarding the bullock of the anointed kohein? The answer is: Rashi explains here that this refers to the western base [to let us know that spilling the blood there impedes. We should not say that he spills the blood there only] because he first passes that side when he exits the Tent of Meeting after completing the sprinklings inside, for the reason that we do not pass over mitzvos. Therefore, the second verse comes to teach us that this is the requirement of the mitzvah, and it is not because of the rule that we do not pass over mitzvos. Rashi in Zevachim (51a) answers in a different way as to why “at the entrance of the Tent of Meeting” is repeated a second time, and we can resolve it differently based on his answer.