Reference for Yevamot 50:6

והא לסטים קתני שנתפס ע"י לסטיות והא יצא ליהרג קתני בי דינא דעובדי כוכבים דלא דייקי וקטלי:

said to those present,<span class="x" onmousemove="('comment',' Lit., 'to them'. ');">¹⁴</span> "Go and tell the wife of Simeon b. Kohen that I killed her husband when I entered Lud" [others Say: When he entered Lud], and his wife was permitted to marry again'!<span class="x" onmousemove="('comment',' Tosef. Yeb. IV; which proves that the evidence of a murderer is accepted. ');">¹⁵</span> He answered them: Is there any proof from there? [It was a case] where he said, 'I was present together with his murderers'.<span class="x" onmousemove="('comment',' But did not himself participate in the crime. ');">¹²</span>

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