Reference for Zevachim 235:8

פשיטא אלא הא קמ"ל דחובות כעין פסח הוא דקרב הא לאו כעין פסח לא קרב ואידך

but they did not offer [obligatory sacrifices] which were not like the Passover-offering.<span class="x" onmousemove="('comment',' E.g., sin-offerings.');">¹²</span> And the other?<span class="x" onmousemove="('comment',' The Rabbis: how do they explain the verse?');">¹³</span>

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