Reference for Yoma 53:4

ואכתי איצטריך סלקא דעתך אמינא כיון דלאו עבודה דמעכבא כפרה היא לא תיבעי כהונה קמ"ל דבעי כהונה

i.e., the work of the priesthood is commanded only from the receiving ['presenting'] of the blood and so on.<span class="x" onmousemove="('comment',' [Since the priests are mentioned only in connection with the presenting of the blood and not with the killing.]');">⁶</span> And he shall lay his hand.

Jastrow