Yahya bin Abi Kathir يحيى بن أبي كثير الطائي · The Book of Financial Transactions

"When two people meet to engage in trade, the transaction between them is not binding until they separate, unless they have chosen to conclude the transaction."

"The Messenger of Allah was asked about (buying) fresh dates with dried dates, and he said to those who were around him: 'Will fresh dates decrease (in weight or volume) when they dry out?" they said Yes,' so he forbade that."

"The Messenger of Allah was asked about (buying) said; 'Will fresh dates decrees (in weight or volume) when they dry out? 'They said 'yes so he forbade that"

"The Messenger of Allah forbade selling a heap of dried dates whose volume is unknown for known volume of dried dates,"

"We used to sell two Sa s of mixed dates for a Sa but the Prophet said (Do not sell) two Sa s dates for a Sa or two Sa s wheat or a Sa or two Dirhams for a Dirham. ,"

"The Messenger of Allah said: 'Gold for gold, weight for weight, like for like; and silver for silver, weight for weight, like for like. Whoever gives more or takes more has engaged in Riba."'