<m.Shebuoth 5.2>  

The oath of deposit how? He said to him: `give me my deposit which I have in thy possession.` [the other replied:] `I swear that thou hast not [anything] in my possession`; or he replied to him; `thou hast not [anything] in my possession,` [and the depositor said:] `I adjure thee.` and he responded, `Amen!`; He is liable. If he adjured him five times, whether before the Beth Din or not before the Beth Din, and he denied, he is liable for each one. R. Simeon [T4] said: what is the reason? Because he can retract and admit.

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