“You may, rather, exact from the foreigner [unfair terms];
but you must not exact [unfair terms] from your brother” (Dt.23:21).
“Exact from the . . . foreigner”—
this is a prescriptive commandment.
“But you must not exact from . . . your brother”—
this is a proscriptive commandment.
Rabban Gamliel says:
Why does the Teaching state—
“you must not exact [unfair terms] from your brother” (Dt.23:21)?
Now hasn’t Scripture already stated:
“Do not exact from your brother unfair terms” (Dt.23:20)?
Actually, [the redundancy teaches that]
there is interest-before-the-fact,
How does this work?
[If] he had in mind to borrow from someone,
and sent him a gift, saying:
[Accept this gift] so that you’ll lend to me—
this is interest-before-the-fact.
[I] he borrowed from someone and returned the money,
and then he sent some [more money], saying:
this is for [your] money that was idle in my possession—
this is interest-after-the-fact.2
“So that HASHEM your God may bless you in all you set your hand to do” (Dt.23:21)—
the verse calls a blessing upon whatever his hands do.3
“On the Land which you are coming to possess” (Dt.23:21)—
as reward for coming, you will take possession.4