Reference for Temurah 6:20

אלא א"ר אבהו

Just as a vain oath refers to the past,<span class="x" onmousemove="('comment',' For if he swears concerning a column of stone that it is gold, this refers to the past, for in the past, before he took the oath, it was a stone, as it is now (Rashi) .');">¹³</span>

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