Midrash for Sanhedrin 129:6

וריש לקיש מ"ט לא אמר כר' יוחנן אמר רב פפא חלוקין הן במיתה

— R. Johanan said: Because both are stated in one negative precept.<span class="x" onmousemove="('comment',' Lev. XIX, 31. Regard not them that have familiar spirits, and wizards. Now in Ker. 2a, where the Mishnah teaches that thirty six offences are punished by extinction, the Gemara explains that the number — 36 — intimates that if one committed them all in one state of unawareness, he is bound to offer 36 separate sacrifices. Since however, those two are forbidden by one injunction, only one atonement must be made for both. Consequently, the two cannot be taught there. ');">⁶</span>

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