THE WHOLE TIME THAT ONE IS PERMITTED TO EAT [LEAVEN], ONE MAY FEED IT TO CATTLE, BEASTS, AND BIRDS, AND HE MAY SELL IT TO A GENTILE, AND BENEFIT THEREOF IS PERMITTED. WHEN ITS PERIOD HAS PASSED, BENEFIT THEREOF IS FORBIDDEN
In other words, not only can one not own leaven during Passover, one cannot even gain benefit from it, for example selling it using it as feed. Now this may be a bit obvious (how can you gain benefit from something you don’t own?) but, the argument goes, it is necessary.
This, by the way, becomes the basis of the now common custom to sell hametz to a non-Jew before Passover – at a time when benefit is still allowed.
But let’s start with the animals. First some terms: “Cattle” (behaymah) refers to domesticated animals. “Beasts” (chayya) refers to wild or semi-domesticated.
For what purpose does he state, CATTLE and for what purpose does he state BEASTS? They are necessary: for if he stated CATTLE, [I might say] that is because if they leave over it is fit for them; but [as for] BEASTS, which if they leave over hide it, I would say [that it is] not [so].
Could the principle be stated using just one example? Maybe not, because of their different habits. Whatever cattle don’t eat, they leave for next time, but whatever beasts leave over they hide for the future. All that hidden food is still in the owners possession even though he can’t see it. So maybe it only needs to say “Beasts.”
While if he stated BEASTS, [I might say] that is because if they leave over they at least hide it; but as for cattle, sometimes they leave over and he [the owner] may not think about it, and so transgress ‘it shall not be seen’ and ‘it shall not be found’ on its account,
So all that leaven for cattle feed is lying around but it is still in the owner’s possession and he may forget about it once he’s fed the cattle.
[and therefore] I might say [that it is] not [so]: thus they [both] are necessary.
I guess they are! But, wait. Aren’t we forgetting something?
What is the purpose of [including] BIRDS?
Because he states CATTLE and BEASTS, he also states BIRDS.
Oh, well. Less rhetorical logic there. But, fine. “Cattle” and “Beasts” and “Birds” it is.