“Neshech”
means “to bite,” because interest “bites” the borrower. Neshech denotes
interest prohibited by the Torah. Examples of neshech are lending four
coins with the stipulation to be paid back five, or lending two
measures of wheat and be paid back three.
“Tarbit”
means “increase.” Tarbit denotes interest prohibited by the Sages. An
example of tarbit is a forward contract for produce, where a buyer pays
now at current prices for goods to be delivered later. The buyer wants
to protect himself from price increase, and it is allowed if the seller
has the goods in stock, or if the market price on the goods is stable.
