The Catholic doctrine on usury and its sixteenth- century codification

From prohibition to the theory of titles

The Catholic Church's position on interest is often summarized as a prohibition that was gradually abandoned. The history is more precise than that. Medieval canon law defined usury as any gain demanded from a loan (mutuum) beyond the capital itself, on the ground that money is consumed in its use and produces nothing by its own nature. Whoever lends money transfers its ownership to the borrower. To demand more than the sum lent is to sell either something that does not exist or the time that belongs to God. From the Third Lateran Council of 1179 onwards, councils enforced the doctrine with spiritual penalties, and those who took interest on loans could receive neither the sacraments nor Christian burial. Thomas Aquinas gave the doctrine its classic form in the Summa theologiae, while the councils of Lyon (1274) and Vienne (1311–1312) added rules on the restitution of usurious gains and on secular laws that permitted usury.¹ From the thirteenth century onwards, theologians and canonists, among them Cardinal Hostiensis, developed a theory of extrinsic titles that justified a payment beyond the capital without calling it interest on the loan. The lender who suffered a loss because the borrower did not repay on time could claim compensation for the damage (damnum emergens). The lender who gave up a profitable investment in order to lend could claim compensation for the profit forgone (lucrum cessans). In certain conditions the risk to the capital (periculum sortis) could be compensated. A penalty clause for late payment (poena conventionalis) was valid if it was not a disguise. Alongside the loan, other contracts allowed capital to earn a return without falling under the prohibition: the partnership (societas), in which the investor shared the risk; the purchase of an annuity (census), discussed below; and the exchange contract (cambium), in which money was exchanged for money at a different place.² The result was a legal order in which the form of the contract decided whether a return was licit. A merchant who wanted to lend at interest had to choose a form that canon law permitted, and confessors, notaries and courts examined whether the form was genuine.

The financial historian Raymond de Roover drew the consequence that scholastic doctrine did not stop the development of banking in Italy. It channelled it into the bill of exchange, which combined a credit operation with a transfer of money between places and therefore escaped the charge of usury, provided that a real exchange took place.³ Chapter A.IV describes the use of the bill of exchange in the Gotthard trade. Its dominance in Italian and Lombard finance until the eighteenth century is partly a product of the usury doctrine.

Notes

1. Wikipedia (consulted as a last resort), "Usury", https://en.wikipedia.org/wiki/Usury ("Lateran III decreed that persons who accepted interest on loans could receive neither the sacraments nor Christian burial"; Aquinas's argument in Summa theologiae, II-II, q. 78). Third Lateran Council (1179), c. 25. Second Council of Lyon (1274), c. 26–27, and Council of Vienne (1311–1312), decree on usury. ↩
2. John T. Noonan, The Scholastic Analysis of Usury (Cambridge, Mass. 1957); Wikipedia (consulted as a last resort), "Usury", https://en.wikipedia.org/wiki/Usury (compensation of the lender "for profit foregone in investing the money himself" among the exceptions enumerated by Hostiensis in the thirteenth century; the article adds that these exceptions were never declared official doctrine by the Church). ↩
3. Raymond de Roover, introduction to Cajetan, "On Exchanging Money (1499)", Journal of Markets & Morality 10/1 (2007), 199–200, https://marketsandmorality.com/index.php/mandm/article/download/278/269 (bankers "had to look for some other way of lending money at a profit", so that foreign banking was tied to "real exchange or exchange by bills (cambium per litteras)"; "the discounting of commercial paper was ruled out by the usury prohibition"). See also Raymond de Roover, The Rise and Decline of the Medici Bank 1397–1494 (Cambridge, Mass. 1963). ↩

For general information only. This article does not constitute legal or tax advice, does not replace advice on an individual case and creates no lawyer-client relationship. It reflects the legal position as of August 2025.