Reference for Chullin 49:10

ומה כלי חרס שאין מיטמא מגבו מיטמא מאוירו כל הכלים שמיטמאין מגבן אינו דין שמיטמאין מאוירן

Indeed, four expositions may be derived from 'toko', by reason of 'toko-tok', 'toko-tok':<span class="x" onmousemove="('comment',' Actually the word 'toko' is mentioned twice in Lev. XI, 33, but it would have served the purpose of the text if in each case the word 'tok' was used. The addition to each word indicates further exposition.');">⁸</span>

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