Reference for Yoma 81:7

והא הכא דלאו שעת לקיחה ולאו שעת עשייה היא וקתני דקבע

i.e., [the designation is made] either at the [owner's] taking [purchasing] or at the offering-up [by the priest]. They raised the following objection: 'And make it a sin-offering'<span class="x" onmousemove="('comment',' Lev. XVI, 9. So literally. E.V. 'offer it for a sin-offering'.');">⁷</span>

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