Reference for Sanhedrin 105:6

אלא מאי בדמיהם דמיהם גמרי מות יומתו למה לי

— He replied: It isdeduced from the phrase 'their blood shall be upon them', for if it is inferredfrom the passage 'they shall surely be put to death', what need is thereof the words 'their blood shall be upon them'? But do you say that it isdeduced from 'their blood shall be upon them'; what need is there then ofthe phrase 'they shall surely be put to death'? — Even as it has been taught:He that smote him shall surely be put to death; for he is amurderer.<span class="x" onmousemove="('comment',' Num. XXXV, 21. ');">⁶</span>

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