Deuteronomy 23:20

To the stranger. This was a dispensation granted by God to his people, who, being the Lord of all things, can give a right and title to one upon the goods of another. Otherwise the Scripture every where condemns usury as contrary to the law of God, and a crying sin. See Exodus xxii. 25., Leviticus xxv. 36, 37., 2 Esdras v. 7., Psalm xiv. 5., and Ezechiel xviii. 8, 13, &c. (Challoner) --- The stranger means the devoted nations of Chanaan, &c., whom God authorized his people to destroy. "Exact usury of him whom thou mayst kill without a crime," says St. Ambrose., (de Tob. c. 15,) though this principle will not always excuse usury. This practice was always considered as unjustifiable, except when God gave permission to his people to get by this means the possession of the property of the stranger, the right to which he had already given to them; unless we may consider, that he only tolerates this practice towards the stranger, on account of the hard-heartedness of the Jews. Christ has now expressly declared it unlawful for any one. See Exodus xxii. 25. (Calmet)