Reference for Pesachim 120:6

מאי הוי עלה אמר רבא פסח ששחטו בשאר ימות השנה לשמו ושלא לשמו כשר דהא סתמו לשמו קאי ואפילו הכי כי שחיט ליה שלא לשמו כשר

Whereupon he said to me, It is not so: If you say thus in respect to another purpose.<span class="x" onmousemove="('comment',' That it disqualifies the Passover sacrifice even if it is also killed for its own purposes.');">¹⁰</span> that is because it operates in the case of all sacrifices;<span class="x" onmousemove="('comment',' All sacrifices, if slaughtered for a purpose other than their own, are disqualified, either wholly, viz., in the case of a sin-offering and the Passover');">¹¹</span>

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