Reuven gives Shimon a gold dinar in exchange for 25 silver dinarim. Who acquires what, and when?
Gold is 'produce' relative to silver. Giving gold for silver is like barter (the gold-giver acts as the buyer of produce). The silver is acquired immediately when the gold is given, before the silver is physically transferred.
Question 2
Shimon gives Reuven 25 silver dinarim in exchange for one gold dinar. Is the gold acquired?
When silver (the 'money') is given for gold (the 'produce'), the gold is NOT acquired yet — it still requires physical acquisition. Either party may retract until the gold is taken.
Question 3
How can a person acquire a promissory note from a colleague?
A promissory note requires both a written declaration of transfer AND physical delivery of the document. Mere handover transfers only the paper, not the underlying debt.
Question 4
A creditor sells a promissory note to a buyer with proper writing and delivery. Can the creditor still waive the underlying debt?
The transfer of a promissory note is only Rabbinic. By Torah law, only the physical document — not the debt itself — can be acquired. The original creditor retains the Biblical right to waive the debt even after 'selling' the note.
Question 5
Three people stand together: lender, borrower, and a third party. The lender says 'give that maneh you owe me to this third person.' Can anyone retract?
The three-party transfer rule is a special halacha: when all three are present and the lender directs the borrower to give to the third party, the recipient acquires immediately and no one may retract. The Sages acknowledged this has no derivable rationale.