The word of Christ doesn’t come any slicker than at Hillsong — the evangelical megachurch, and Christian business success story, based in Sydney’s Hills district.

Started 30 years ago by pastors Brian and Bobbie Houston with a congregation of just 45, the church has since grown into an international phenomenon with revenue in the tens of millions.

Hillsong now claims to be the largest church in Australia, with a weekly attendance of 20,000 in Sydney. Backed by its enthusiastic founders, polished marketing effort and powerhouse music label (which boasts numerous ARIA chart topping hits), it’s hard to argue otherwise.

They’ve even managed to crack the overseas market, setting up outposts in London, Kiev and the spiritual home of Pentecostalism, the United States. The Houstons travel the world giving speeches and spreading the word at the church’s offshoots and allies (they were offshore when The Power Index asked for an interview).

“They’re an Australian multinational,” says Andrew Jakubowicz, professor of sociology at Univeristy of Technology Sydney, who notes their ability to recruit significant numbers.

Part of that may come down to the way they do religion. To many of its followers, Hillsong’s youthful high energy song-and-dance style is a revelation, particularly when compared with the fire and brimstone approach sometimes preferred by the more traditional sects. At the last census, 238,000 Australians identified as Pentecostal — up one fifth. Many of those attend charismatic churches such as Hillsong or Christian City Church.

Hillsong is also particularly savvy when it comes to selling their message. Its church and music arms boast armies of followers on social media; live shows have been watched by millions on YouTube. There’s even an app, with Brian Houston’s sermons available to download via iTunes. Earlier this year, marketing website mUmBRELLA named Hillsong one of Australia’s most powerful brands.

Of course, not all of this comes free. The church does a roaring trade for merchandise, particularly its music which it says has sold more than 12 million records worldwide. Followers can attend the hugely-popular travelling Hillsong conference, which takes key speakers around the world. An adult ticket to next year’s event in Sydney will set you back $239.

And then there’s the church-ordained process of tithing (which followers can do securely online). As one observer put it: “They’ve got a swipe machine under every row, so you can put in your credit card every time you sit down and pray.”

According to Marion Maddox, an expert in politics in religion at Macquarie University, the crossover between the corporate world and megachurches like Hillsong is “seamless”.

“They and other growth churches like them around the world have produced a form of religion that meshes precisely with late capitalist ethos,” Maddox tells The Power Index. “You can walk into a Hillsong service and you don’t really know whether you’re at a church service or a corporate growth seminar.”

Hillsong’s links with the business world are well known. Most famous are its ties with the founders of Gloria Jeans, which was boycotted this year when it was discovered the coffee franchise had donated to the Australian Christian Lobby. Politically, it has also many friends. John Howard opened its 3500-seat convention centre in Baulkham Hills, while Peter Costello, Alexander Downer, Kevin Andrews, Bob Carr and Peter Dutton have all attended its convention.

Whether this translates into political outcomes is still unclear. Hillsong’s conservative social views fit in with most other Christian churches, so many of their battles are being fought for them. What’s more clear is how fast they — and others like them — are growing.

As Andrew Jakubowicz notes: “I don’t know what they’ve delivered politically, but they’ve clearly made an impact in relationship to the traditional landscape of Australian religions.”