Reference for Yoma 13:2

אמר רב ששת מנא אמינא לה דתניא היה עומד ומקריב מנחת העומר ונטמאת בידו אומר ומביאין אחרת תחתיה ואם אין שם אלא היא אומרין לו הוי פקח ושתוק

and it became unclean in his hands<span class="x" onmousemove="('comment',' The rendering in our text seems defective. In Men. ');">⁴</span> let him tell and another one is brought in its place. And if there be none but this, one would say to him: 'Be clever and keep quiet'.<span class="x" onmousemove="('comment',' Since no substitute is available, silence is wisdom, for the priest's frontplate procures forgiveness for such mishap. V. infra.');">⁵</span>

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