This is one of the most thought-provoking books any Christian who takes the Bible seriously as a guide to all of life can read on the subject of interest-taking or usury. Gary North has interacted with this book somewhat and rejects the author's thesis, which I think can be summarized as "interest-taking (i.e., usury) is only to be used as a means of subjugating the borrower, and thus must be rejected by Christians in their dealings with other Christians." I put that in quotation marks but it is NOT a direct quote from the book, which I don't have in my possession at the moment, and my apologies to the author if I have not summarized his thinking fairly, but in any case that's at least close to what his position is. Many Bible-believing Christians take the position that the biblical prohibition is actually only against the taking of interest on CHARITABLE loans, but the taking of interest on business loans is legitimate, even if both parties are Christians. Mooney looks at the Bible and concludes that the Bible in fact denies the legitimacy of charging interest to fellow believers under any circumstances.
(And furthermore he seems to apply this concept to rent, as well, although that aspect is not dealt with extensively in this book.)
In modern society, these are very hard words to hear, and I have really struggled with (or perhaps against) the book's thesis. However, the more I keep coming back to this in my mind, the harder I am finding it to continue rejecting the author's conclusions. A great deal of the argument on both sides comes down to how Jesus' parable of the talents is to be understood. Is that parable affirming the legitimacy of taking interest, or denying it? For a long time I thought that the parable was affirming the legitimacy of taking interest, but after considering the author's arguments, I am inclined to think he is right -- the parable is rejecting the legitimacy of interest-taking. Of course, if one assumes that it all came from one Author, the parable cannot be considered in isolation and needs to be considered together with everything else in the Bible.
(Although it is more or less outside the scope of this book, I am LESS convinced that the same prohibition applies by logical extension to rent. However, at least concerning the charging of interest on money-lending, the author's arguments deserve a serious hearing among all Bible-believing Christians.)
Part of the reason I came around to being more sympathetic to the author's views is my gradual development of appreciation for the fact that in the modern world, MONEY IS DEBT. (Do a Google search on the phrase "Money as Debt" to find a short film by Paul Grignon that explains this in an easy-to-understand manner. That film's proposals for a solution are in error, but its explanation of what is wrong with the modern monetary system is very good.) The world is a closed system, and as all money is created by bankers from debt -- meaning it accrues interest -- the only way to pay off the principal and the interest in entirely is to create more money. But the creation of more money necessarily means the creation of more interest-bearing debt, and the vicious cycle never ends. As time goes by, the insane "logic" of this approach moves inexorably toward the totally absurd conclusion that eventually, ownership of the entire world must be transferred to the bankers. Now the world is a closed system but it is also a very large system -- large and still immature. So it takes a long time (many generations) for these implications to be fully worked out. But worked out they shall be, eventually. So when we see the absurdity and the evil of the ultimate conclusion -- that everyone in the world should be reduced to serfs working on the bankers' plantations, it makes it a lot easier to go back to the biblical text and see why God prohibits usury.
I am still not 100% certain as to whether I want to embrace Mooney's essential thesis, but I am strongly inclined to think he is probably correct. The question then arises, "Is it workable?" I think the answer to that is yes, it can be done. However, if this is what God is commanding at this point, obeying God in this matter would completely transform modern culture into something very different from what it is now. And perhaps that is exactly the point! This is "just one commandment" but it is one that would radically transform the modern world if it was obeyed (assuming, of course, that Mooney is correct). Christians must not shy away from careful consideration of this subject. It would NOT be adequate to obey God on everything else (not that we do so, of course) but then to fail to obey God on this one point. After all, as the Scripture tells us, the law of God is a unified whole and it is not possible to abrogate it at one point without abrogating the whole.
I'm very grateful to the author for this extremely thought-provoking work and I recommend it, and indeed all of his writings relevant to this topic, to Bible-believing Christians and to anyone else who wants to study what the Bible teaches on this subject. At the time of this writing, the book is no longer in print; however, unused copies may still be available and one way to find them may be to go to the various blogs where C.S. Mooney's writings are discussed and inquire with the blog author as to whether he knows where Mooney's books can be obtained.
For what it's worth, I work in the real estate securitization department of one of Japan's largest securities companies. (Believe me, I feel the irony every day.)