Sahih Muslim 4073
صحيح مسلم#4073SahihAbd al-Rabman b. Abia Bakra reported on the authority of his father that Allah's Messenger (ﷺ) forbade the sale of gold for gold, and silver for silver except equal for equal, and commanded us to buy silver for gold as we desired and buy gold for silver as we desired. A person asked him (about the nature of payment), whereupon he said:It is to be made on the spot. This is what I heard (from Allah's Messenger (may peace be upon him)
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Every narration in Sahih Muslim is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 22:112