Reference for Bava Batra 67:2

אמר (להו) רבי אבא הוי מחויב שבועה שאינו יכול לישבע וכל המחויב שבועה שאינו יכול לישבע משלם

Shall we administer an oath to him? — But he admits that he snatched the article, and since he admits that, he is, as far as this case goes, a robber.<span class="x" onmousemove="('comment',' And therefore he is disqualified in this case from taking an oath in court. ');">²</span>

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