Biblical scholars have given much time to researching and speculating about whether charging interest is absolutely forbidden by Old Testament law. The most natural translation of Ezek. 18:8a may be the NASB: "He does not lend money on interest or take increase." Until well after the Reformation, Christians universally understood the Bible to prohibit charging interest on loans. Of course, this would severely hamper the productive deployment of capital, both in modern and ancient times, and contemporary interpreters seem disposed to soften the prohibition to excessive interest, as the NRSV does. To justify this further softening, some have argued that origination discounts (what we now call "zero-coupon bonds") were permitted in ancient Israel, and that only additional interest was forbidden, even if the loan was not repaid in a timely manner.[1]As with the topic of surety above, it is beyond the scope of this article to assess the legitimacy of the entire modern system of interest.[2] Instead, let us look at the outcome in either case.

If the stricter interpretation holds, then people with money will face the choice of whether or not to lend money at all. If they are not allowed to take interest, and not allowed to repossess surety, then they may prefer not to lend to anyone. But that answer is forbidden by God: "You should rather open your hand, willingly lending enough to meet the need, whatever it may be" (Deuteronomy 15:8). Jesus repeats and even expands this command in Luke 6:35: "Love your enemies, do good, and lend, expecting nothing in return." The loan is primarily for the benefit of the borrower, not the lender. The lender's fear that it may not be repaid must remain a minor concern. The potential lender has the capital, and the potential borrower needs it.

On the other hand, if we accept that the modern system of interest is legitimate, this principle still applies. Capital must be invested productively; it cannot be hoarded because of fear. This is the literal meaning of Jesus' parable of the talents (Matthew 25:14-30). God has promised Israel, his treasured possession,  that he will provide for their needs. If individuals find themselves with capital to spare, they owe it to the God of provision to employ it — whether by just investment or by donation — for the provision of those who are in need. Economic development is not forbidden — just the opposite: it is required. But it must be of productive benefit for those who need capital, and not merely for the self-interest of those who possess capital.