Reference for Zevachim 20:6

אמר מר אמר לו ר' יהושע חוזרני חלילה ולמיהדר דינא ולייתי במה הצד

[which likewise intimates,] for its own sake it is valid, and if not for its own sake, it is invalid; [then] in the case of a guilt-offering too it says, It is [a guilt-offering],<span class="x" onmousemove="('comment',' Lev. VII, 5.');">⁵</span>

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