An example of this is the dove: its equivalent is a sheep, so a sheep is the compensation for a dove, because Allah, Exalted is He, says: “Then the compensation is an equivalent from livestock of what he killed” [al-Ma’idah: 95]. The resemblance between them lies in the way they drink water: the sheep gulps it down, and the dove drinks it in gulps, like an infant suckling at the breast. As for a chicken, when it fills its beak, it raises its head so that the water may go down; but when a dove puts its beak into the water, it does not raise its head until it has quenched its thirst. The sheep does likewise.
Thus, if a person in the state of ihram kills a dove, we say: You have the choice: slaughter a sheep and give it in charity to the poor of the Sacred Precinct; or appraise the sheep in dirhams, and instead of the dirhams give food—do not give the dirhams themselves—because Allah says: “or an expiation: feeding needy people.” If we appraise the sheep at two hundred riyals, and appraise the food at one riyal per sa‘, then it comes to two hundred sa‘s, equivalent to eight hundred mudds. We say: if you wish, give the food; and if you wish, forgo the food and fast eight hundred days, since there is one day for every mudd. He will therefore choose either the sheep or feeding the poor, because fasting would be arduous. But, praise be to Allah, the matter is broad, since he has been given a choice.
Who determines the equivalent?
The answer is that Allah, Exalted is He, says: “as determined by two just men among you” [al-Ma’idah: 95]. “As determined by”—that is, the equivalent—“two just men among you.” One person is not sufficient; two are necessary. In the following chapter, Allah willing, it will come to us that whatever the Companions, may Allah be pleased with them, ruled upon must be referred back to, while in cases upon which the Companions did not rule, two men are to determine it.
His statement: “And, regarding that which has no equivalent, between feeding and fasting”: this is the second category.