Reference for Sanhedrin 154:6

א"ר אשי הלכך אפילו סמנין בשוק א"ל רב אחא בריה דרבא לרב אשי נזדמנו לו סמנין מהו אמר ליה הרי יצא מבית דין זכאי

R. Aha the son of Raba asked R. Ashi: What if he came across the balsam by chance?<span class="x" onmousemove="('comment',' When smitten, he neither possessed nor could procure it. But by some happy chance, he subsequently obtained it, and though he could have healed himself therewith, did not. Do we say, since when the attack was made, murder was its probable outcome, he is liable; or since he could have healed himself, he is not. ');">⁴</span>

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