Bava Metzia 18 - One Found Bills of Divorce, Sickbed Will, Etc.
If one found bills of divorce, or bills of emancipation of slaves, or sickbed wills, or gift documents, or receipts - he should not return them to the recipients named on them. It is possible that they were written with the intent to give them, but the author reconsidered and decided not to give them, and it was he who lost them. The above documents effect the transaction, thus, if the writer lost them, they don't take effect.
Wills are generally not effective in Torah law; unless formal gift has been made before death, property passes automatically to the rightful heirs defined by the Torah. Sickbed will is an exception.
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