I'm going to highlight a few spots of this to the degree where if you say any bold text that's my emphasis added, not Trueman's.
Looking back on the creepy cults of the 70s and the self-indulgent excesses of the televangelists of the 80s can be a little like watching an episode of some ghastly 'reality TV show': as the freaks and frauds parade on the television screen, that subtle sentiment of "I thank thee Lord that I am not like other men" is never far from the surface.
When it comes to cults and televangelists, of course, evangelical Protestants have an obvious foundation for assuming their superiority to the wild-eyed megalomaniacs and the superannuated mullet-haired mountebanks of the TV revival brigade: orthodox theology. The scoundrels are all deviant or downright heretical. We have the right theology, so we cannot be cultists or corrupt, can we? Sadly, that is not so.
In fact, as Paul himself makes clear, the gospel - the true gospel - can be peddled for power and for profit. To borrow Lutheran terminology, just because the product being sold is the theology of the cross does not mean that the salesman is not a theologian of glory. Cults and corruption are reflections of certain cultures, not of confessions. They can be as orthodox on paper as the Chalcedonian Definition but as perverted in their practices as a poker game run by a man called 'Honest John.' So just because somebody preaches the gospel, uses the name of Jesus every other sentence and cries when they talk about the lost does not guarantee that they are not a cult leader or simply in it for what they can get out of it.
The key is the culture. One must ask cultural questions of such men, not simply doctrinal ones. Is the culture of their church or organisation transparent? Are there clear lines of accountability which flow both ways, from the leadership to the grassroots and from the grassroots to the leadership? Is opposition to leadership decisions addressed in an open fashion or via thuggish backroom manoeuvres and public derision and isolation of critics? And one interesting question which I remember a pastor once asking in a pulpit when I was a college student: how far above the average economic level of the congregation or funding constituency does the leadership live? That little old lady putting her ten dollars in the plate each Sunday or sending in her pledge -- is she funding a lifestyle for functionally unaccountable leaders which is lavish beyond words and built on gospel rhetoric, on not-for-profit tax breaks and on an overwheening sense of entitlement? That can be quite an interesting gauge of whether the church or ministry takes seriously its role as steward of the money it receives. It is, after all, easy to prostitute yourself to the prosperity gospel when your own prophecies of material wealth are effectively underwritten by the desperate dreams of the poor and destitute which you yourself have helped to create and upon which you prey with a depraved and insatiable hunger.
Cultists and con-men are identifiable only by their culture, not by their confessions.