A small cloud hangs over the drab Victorian church of Holy Trinity Brompton, in west London. It's tempting to see it as the wisp of suspicion that, rightly or wrongly, lingers over Britain's most powerful evangelical church. This is the birthplace of Alpha, the "informal, friendly and fun" course now practised in 169 countries, which numbers the new Archbishop of Canterbury among its recruits.
Ten days ago, Justin Welby was enthroned as leader of the Church of England. It was a new high in the history of HTB. The 56-year-old former oil executive is the first resident of Lambeth Palace to have found God through rock music and group therapy. Twenty years ago, evangelical Christianity was a fringe activity, associated with loony American cults. Today, 1.2 million Britons have attended an Alpha Course, and thousands attend HTB services every Sunday. It's British Christianity's biggest success story.
I've come to Brompton to meet Nicky Gumbel, vicar of HTB and chief architect of the Alpha Course. If Welby is the Church of England's new leader, Gumbel is his spiritual father. The two men share remarkably close stories, having known each other for more than 40 years. At 57, Gumbel is roughly the same age. Both attended Eton and Trinity College Cambridge, before pursuing high-powered careers which they gave up for the church.
The rectory at HTB is a classic Church of England affair. Not a handsome Georgian number, but knocked up in the Sixties in glass and concrete. Inside, it is light, airy, and tastefully upholstered in expensive fabrics. Gumbel is tall and handsome, with curly greying hair; he speaks with a clipped accent. He met his wife, Penny, through the church, and they have three grown-up children; the model of an active Christian family.