He that by usury and unjust gain increaseth his substance,.... By biting and oppressing the poor; letting him have money at an exorbitant interest, and goods at an exorbitant price, and so increases his substance in this scandalous manner; hence usury is in Le 25:36, called "increase", and by the Greeks tokov, a "birth", because money is the birth of money, as Aristotle observes; and so by the Latins "foenus", as if it was "foetus" , "a birth".
The word for usury here signifies biting; and so usury, with classical writers , is said to bite; and while it increases the substance of the usurer, it lessens and devours that of others;he shall gather it for him that will pity the poor; not for himself, nor for his posterity; but for such, though not intentionally but eventually, as will make a good use of it, and distribute it to the necessities of the poor.