Reference for Chullin 202:12

שבת קביעא וקיימא יום הכפורים בי דינא דקא קבעי ליה

It was a time of religious persecution,<span class="x" onmousemove="('comment',' And the observance of the Day of Atonement in its proper time was proscribed.');">⁹</span>

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