If a fungible thing is given to someone in such a way that it becomes his own and is to be returned later on in kind only, no profit may be made by reason of the contract itself; but in lending a fungible thing it is not in itself illicit to contract for legal interest, unless this be manifestly excessive, or even for a higher profit if a just and adequate title be present.
22While also including the modern definition of usury as excessive interest, it would seem this official law of the Church (which was in effect until 1983) still remained faithful to the Church’s teaching as properly understood according to the theory of extrinsic titles outlined by the scholastics. In fact, the 1917 Code also provided "that several penalties be imposed on those convicted of usury, which is listed with such crimes as murder, rape, and robbery."
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