Abu Ayash Zaid reports: He asked Sayyiduna Sa’d bin Abi Waqqas (may Allah be pleased with him) about exchanging one type of barley for another type. He asked which of the two is superior. He replied: The white one. Then Sayyiduna Sa’d bin Abi Waqqas (may Allah be pleased with him) forbade him from this and explained that he had heard the Noble Prophet (peace and blessings be upon him). He was asked about selling fresh dates in exchange for dry dates. The Noble Prophet (peace and blessings be upon him) asked: Do fresh dates decrease in quantity when they dry? The questioner replied: Yes. So the Noble Prophet (peace and blessings be upon him) forbade him from this.