Wherever true Christianity spreads, it must cause diligence and frugality, which, in the natural course of things, must beget riches! And riches naturally beget pride, love of the world, and every temper that is destructive of Christianity. Now, if there be no way to prevent this, Christianity is inconsistent with itself and, of consequence, cannot stand, cannot continue long among any people; since, wherever it generally prevails, it saps its own foundation.

John Wesley preached this sermon in Dublin in 1789. Transport him forward through time to the parking lot of a gleaming glass and steel megachurch, amidst the BMWs and SUVs, and it's not hard to imagine him standing on the bed of a rusty pickup truck, preaching the same sermon. Is Wesley, then, a prophet for our times? Does this sermon encapsulate the story of North American evangelicalism?

At the beginning of the 20th century, evangelicalism gave up much of its wealth and social status so that it could be more faithful to the gospel. A century later, North American evangelicalism has recouped its lost wealth, and then some. In most American neighborhoods today, nearly all the new large church buildings have been built by evangelicals. The new wealth of evangelicalism is even more pronounced in the parachurch world. The largest charitable organization in the nation—with an annual budget of over $2 billion—is the Salvation Army, a unique combination of holiness denomination and parachurch agency devoted to human services. Of the nine largest parachurch organizations in the U.S. devoted to spreading the gospel, eight are evangelical, with combined 1998 budgets of $729 million. Of the seven largest communications media agencies, six are evangelical, with total ...