Could he intend the animal by the meat?

The answer is: No, that is not possible, because this meat cannot become an animal again. But it is possible to intend the meat by the animal: he may slaughter it and eat its meat. Thus, if this hadith is authentic, it is to be understood as referring to the case in which a person intends the animal for its meat.

His statement, “and it is valid with an animal of a different genus,” means, for example, that one may sell sheep meat for a cow. For the difference of genus falls under the Prophet’s statement: “When these categories differ, then sell as you wish, provided that it is hand to hand” (1). Thus, if he sells edible meat for a donkey, it is permissible, due to the difference in genus and also in intended benefit.

“It is not permissible to sell grain for its flour, its parched flour, or its raw form for its cooked form; nor its original substance for its juice, its pure form for its mixed form, or its fresh form for its dried form. …”

His statement, “It is not permissible to sell grain for its flour,” applies even if they are equal in weight.

For example, a person has a sāʿ of wheat and sells it for a sāʿ of wheat flour. This is not permissible because equality is not established, since the particles of the grain spread out when it is ground.

If he says, “I will add to the flour whatever amount makes its weight equal to that of the grain,” we say: This too is not permissible, because the applicable measure for grain and flour is volume, not weight; therefore, the sale is invalid.

Some scholars said that there is nothing wrong with it if they are equal in weight, because their equality in weight indicates that they were equal in volume while still grain. They cited two proofs for this: