Reference for Bava Metzia 6:2

אבל העדאת עדים דליכא למימר הכי אימא לא קמ"ל ק"ו

and that he has not done so because of a desire to put the claimant off for a time, thinking: 'When I shall have money, I shall pay him.' Therefore the Divine Law imposes an oath upon him, so that he may admit the whole claim. But as regards the testimony of witnesses, where this argument does not apply,<span class="x" onmousemove="('comment',' As the defendant denies the whole claim, and if he is dishonest he may also be ready to commit perjury. ');">²</span>

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