Reference for Keritot 28:16

כגון שנפלה לו ליבום

If so, what means: HAD COMMITTED TRANSGRESSION? - He committed transgression In that she was his son's daughter-in-law, which is a forbidden relation in the second degree,<span class="x" onmousemove="('comment',' I.e., one enacted by rabbinical law.');">⁸</span>

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