If I offer to loan you 100 gold grams on the condition that you repay me 150 gold grams two years from now, where is the theft or lie? If I made the same offer to nine other persons, it may be the case that four of them cannot repay, in which case I'd have loaned 1000 and gained 900 for a loss of 100. A bird in the hand is worth two in the bush. A dollar today is worth two at a later date. One hundred gold grams may, all else equal, be on the market worth one hundred fifty gold grams two years from now simply based on time preference. I might have a lower time preference and you may have a higher, and so we both win by this exchange. Where does the extra come from? From consumers buying from your productive enterprise, from your own savings, from wherever you intended to get the other fifty. The loan does not imply that there is a continual transfer from you to me, without any chance of the fifty being spent back into consumption by the lender. The lender needs to eat too. To summarize: usury involves a fair and free exchange, risk on the part of the lender, and time preference of both parties. Therefore there is no theft or lie involved.