Reference for Chullin 166:14

בעפר מלמד שהשוחט צריך שיתן עפר למטה ועפר למעלה

If he were to place [dust upon the altar] and decide to leave it there,<span class="x" onmousemove="('comment',' Lit., 'renounce it', so that it becomes part of the altar.');">⁷</span>

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