Reference for Sotah 15:9

אמר אביי ואיתימא רב כהנא לא קשיא כאן בכהן אחד כאן בשני כהנים

Our Rabbis have taught: They do not give two suspected women the water to drink at the same time, so that the heart of one should not become defiant because of the other.<span class="x" onmousemove="('comment',' One may be guilty and the other not. The first may refuse to confess because the other does not confess. ');">⁹</span>

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