Thomas Aquinas: On Usury, c. 1269-71
Of the Sin of Usury, Which is Committed in Loans:
To take usury for money lent is unjust in itself, because this is to sell what does not
exist, and this evidently leads to inequality which is contrary to justice....
Now money, according to the Philosopher (Ethics v, Polit. i) was invented
chiefly for the purpose of exchange: and consequently the proper and principal use of
money is its consumption or alienation
whereby it is sunk in exchange. Hence it is by its very nature unlawful to take payment
for the use of money lent, which payment is known as usury: and just as man is bound to
restore ill-gotten goods, so is he bound to restore the money which he has taken in
A lender may without sin enter an agreement with the borrower for compensation for the
loss he incurs of something he ought to have, for this is not to sell the use of money but
to avoid a loss. It may also happen that the borrower avoids a greater loss than the
lender incurs, wherefore the borrower may repay the lender with what he has gained. But
the lender cannot enter an agreement for compensation, through the fact that he makes no
profit out of his money: because he must not sell that which he has not yet and may be
prevented in many ways from having....
It is lawful to borrow for usury from a man who is ready to do so and is a usurer by
profession; provided the borrower have a good end in view, such as the relief of his own
or another's need.
From: St. Thomas Aquinas, Summa Theologica, trans. Fathers of the English
Dominican Province, (London: R. T. Washburne, Ltd., 1918), pp. 330-340, reprinted in Roy
C. Cave & Herbert H. Coulson, A Source Book for Medieval Economic History, (Milwaukee:
The Bruce Publishing Co., 1936; reprint ed., New York: Biblo & Tannen, 1965), p. 182
Scanned by Jerome S. Arkenberg, Cal. State Fullerton. The text has been modernized by
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