The only surprising feature of Donald Trump’s first year in office is that it has been entirely predictable. So when I mention to colleagues that I have been researching Trump’s religious faith, reactions vary from mild scoffing (“I thought he was his own religion”) to bafflement and surprise. But Trump has a faith. And if you want to know how the next few years of his presidency will pan out, understanding Trump’s religion is an important key.

Start with his inauguration ceremony. Pastor Paula White was one of the clergy nominated to pray for Trump on the day. A televangelist and exponent of the “health, wealth and prosperity” movement, she preaches the “prosperity gospel”, an unorthodox approach to Christianity that says God wants people to be rich, and that he makes them wealthy as a sign of his blessing. So the richer you are, the more obvious it is that God loves you, and the stronger your faith is.

White teaches that God rewards “faithful” people who invest in His promised providence. You invest by making deposits – faith, prayers and gifts of money – to God (the church, naturally, is the “steward” of your financial gifts). So if you want to be healthy and wealthy, all you need to do is give, and then believe, and all your heart’s desires will be realised. The more you invest, the greater the likely rewards.

The president believes 'make America great again'. If it doesn’t happen, it's not his fault. It’s yours

Others chosen by Trump to pray at his inauguration include the conservative Catholic cardinal Timothy Dolan (who is outspoken on pro-life issues) and the Rev Franklin Graham, son of the evangelist Billy Graham. It was Graham who told millions of America’s evangelicals that they could vote for Trump with a clear conscience since Trump was comparable to the ancient Persian ruler Cyrus, mentioned in the Old Testament.

How does this Cyrus-Trump comparison work? Cyrus was an all-conquering Persian king. Around 550BC he overthrew the Babylonians, who had persecuted the Jews by driving them into captivity, and stripped them of their freedoms. When Cyrus conquered the Babylonians, he released all the captives. Moreover, he respected the traditions of the lands he captured and ruled with a lean, decentralised administration. For American evangelicals, the rule of Cyrus is one that worked to the advantage of all its subjects – and especially God’s chosen people. Cyrus is the only foreign ruler referred to as “Messiah” (literally “His anointed one”) in the Old Testament (see Isaiah 45:1), and is the only non-Jewish figure in the Bible to be given this accolade. Graham, in signalling that Trump was a kind of Cyrus, was simply saying that evangelicals and fundamentalists could now rid themselves of a once dominant, centralising liberal hegemony, and reclaim their religious freedoms. They could do this even by voting for someone who manifestly doesn’t share their evangelical faith.

But Trump, in this equation, therefore emerges as a liberator-messiah-ruler, and Washington as a kind of centralising Babylon. And you don’t need to be a genius to work out that Trump is the Cyrus who delivers all God-fearing Americans from that awful prospect of the Whore of Babylon (Book of Revelation, chapters 17 and 18) living in the White House. “Drain the swamp” and “lock her up” are therefore implicit religious rallying calls, not just injudicious hate speech. These are the chants of the self-proclaimed righteous.

Donald Trump at the 90th birthday celebration of Norman Vincent Peale. Photograph: Tom Gates/Getty Images

But Trump’s political rhetoric can be traced back further, to the specious singularity of his religious roots. Norman Vincent Peale, the pastor of New York’s Marble Collegiate church, was Trump Sr’s pastor and presided at the wedding of Trump and Ivana in 1977. Peale’s bestselling 1952 book, The Power of Positive Thinking, manifestly shaped the world of the Trumps. The book also launched the motivational thinkers’ industry, and its practitioners are businessmen just like Trump. Marketed on confidence, pragmatism, expectations of exponential growth and realising your dream, ambition or vision, it also shaped numerous Christian evangelical and fundamentalist ministries.

So, The Power of Positive Thinking shaped the church growth movement, the “health wealth and prosperity” movements, and many other expressions of capitalist-friendly evangelicalism and fundamentalism. The hypothesis was simple: if you believe it enough, have the faith for it, and keep saying it enough, it will be so. Your mind and your language, if fully positive, will ultimately reify your goal.

In some respects, then, we already know how Trump’s mantra – “Make America great again” – will pan out. The president believes the vision. If it doesn’t happen, it won’t be his fault: it will be yours. Not enough people have faith; too many doubt. Blame the faithless.

To some, this may seem perfectly rational. American churchgoing embraced the free market long ago. The rejection of any religious establishment opened the way for competition between individual churches, and then produced the extraordinary organisational and theological span that distinguishes the US from all previous Christian societies. The price of this exuberant expansiveness is doctrinal incoherence. If there is a bespoke Christian faith for every customer wanting their own personal tailored religion, then faith will mean almost anything – and therefore almost nothing. And this has effects that ripple out far beyond believers. It also relates to our emergent post-society era. A religion that is responsive to the pressures of the market becomes profoundly fractured. In the end, a market-driven religion gives rise to a market-driven approach to truth.

Trump’s interior religious landscape is a kind of politico-spiritual Ponzi scheme, and his politics flow from this. Opportunism, pragmatism and positivism are the lessons Trump learned from Peale’s pulpit. And as we know, operators of Ponzi grab the attention of investors by offering short-term returns that are either abnormally high or unusually consistent. Ponzi schemes rely on a constant flow of new investors to continue to provide returns. When the flow runs out, the scheme implodes.

The implicit religion of America is branded on every dollar bill: “In God we trust”. Godly providence and worldly prosperity are spiritual and material realities for Americans, and politics and pragmatism their agents. Trump is merely the natural progeny of a nation where the intercourse of God and mammon is seldom questioned.

So what is to be done about Trump’s material-centred religion? Here I take seriously the counsel of Trump’s predecessor. It’s all about perspective. We can see this era as a blip, a comma. This age will pass. But equally, we cannot afford to be complacent.

We need our leaders to be social visionaries, political realists and exemplars of virtue and integrity. Trump, as we know, is wanting in each and every one of these departments. Over the next few years of Trump’s presidency, ennui and disenchantment will set in among hardcore supporters. They will eventually become the faithless followers. Too many investors will want a return. And when there are no new gullible recruits, Ponzi schemes, even political ones, unravel.

• Martyn Percy is a Church of England priest and the dean of Christ Church college, Oxford