We say to him: Sell the bread and buy jarīsh, as the Prophet ﷺ said regarding good dates and inferior dates (1).

His statement, “flours and breads”: flours is the plural of flour, and breads is the plural of bread.

His statement, “and oils”: this is based on the view that ribā applies to oil, because it was sold by volume in the time of the Messenger of Allah ﷺ and is therefore a volumetric commodity. Every liquid is measured by volume, such as rendered fat, oil, and the like. But if we hold that ribā does not apply to oil, then there is no harm in selling some of it for some of it, whether in unequal or equal amounts.

His statement, “and meat”: meat, too, consists of different genera. Camel meat is one genus; sheep meat is another; cattle meat is another; goat meat is another; rabbit meat is a genus; and gazelle meat is a genus. Meat is sold by weight, so it is not permissible for me to sell one kilogram of sheep meat for two kilograms of sheep meat, since they are of the same genus and disparity is therefore not permitted.

However, one kilogram of beef may be sold for two kilograms of lamb, because the genera differ. This, too, is based on the view that ribā applies to meat, and this is a sound view if we are in a land where meat is a staple food. But if we are in a land where meat is not regarded as a staple food, then ribā does not apply to it, because it is not a staple. The established position of the school is that ribā applies to it because it is sold by weight; according to the school, the effective cause is measurement by volume or weight. Thus, if I sell you one sheep for two sheep—