A couple of decades ago, a young man stood at the back of a church in Kensington. As the vicar hushed the church for the moment of silence at the fixed time in the service that preceded the weekly “spontaneous” outpouring of “tongues”, the man unleashed a torrent of ecstatic but incomprehensible sound that echoed around the neo-Gothic arches. “Truly, God is with us,” murmured the vicar as the predominantly white congregation said “Amen” and “Praise the Lord”.

An analysis of the tape — services at this church were often recorded — showed that the man had been speaking Arabic, was lost and was seeking directions.

This story was current in London church circles in the 1990s, when a resurgence of charismatic pentecostalism was making itself felt throughout the mainstream churches as well as on the fringes. In a movement inspired by the “Toronto Blessing” and which began in an evangelical church in Toronto, congregations in North America and the UK began experiencing an upsurge of all the gifts listed by St Paul. Some were collapsing en masse on the floor in a phenomenon known as being “slain in the spirit”, barking like dogs or honking like pigs, and even claiming that tooth fillings had been turned to gold.

As this attracted inevitable ridicule, and even Christian leaders began to suspect that an influence from the opposite end of the spectrum to the Holy Spirit might even be at work, the more extreme manifestations of God’s presence in worship receded. But speaking in tongues remained popular.

During this time I visited an evangelical church in Wimbledon to see for myself what was going on. This was a largely white, middle-class congregation meeting in a school hall. It was an intense experience, and there was much murmuring in tongues. In years of attending different churches, including charismatic ones, I have never felt visited by the gift of tongues. But at one moment in this service, worshippers around me began falling to the floor like ninepins. I felt blood drain from my head and the room began to grow small, as if receding into some infinite spot. I ran for the door, stepping over dozens of bodies on the way out, and never went back. The most bizarre part was seeing people drinking coffee and chatting at the back, as if nothing odd was happening, while their friends lay on the floor around them.

According to research published today, Pentecostals now outnumber Methodists at church services in England. The proportion of people who speak in tongues is higher in black-led Pentecostal churches, but even so there are probably several hundred thousand in this country alone.

And the number is growing. Research shows that while many liberal churches continue their inexorable decline, the growth among evangelicals and charismatics is in some cases exponential. Although not all these will practise speaking in tongues, this combined group makes up more than a third of the Church of England alone, with nearly 300,000 worshippers.

Speaking in tongues is one of the “gifts of the spirit” listed by St Paul in his letters in the New Testament. Others include the gifts of prophesy and of leadership. Its precedence in the Church is detailed in the Acts of the Apostles, when Jesus’ disciples at Pentecost were “all filled with the Holy Spirit and began to speak in other tongues, as the Spirit gave them utterance”. According to St Luke, the author of Acts, the Apostles suddenly became multilingual when the Holy Spirit’s “tongues of fire” appeared above their heads. They were able to address vast crowds in their own language.

For much of the church’s history, speaking in tongues was viewed with suspicion by the mainstream, especially in buttoned-up Britain, where any manifestation of religious excitement or enthusiasm was frowned upon. It was nearly a century ago, in a black-led church in Los Angeles in 1909, that glossolalia made its reappearance in modern times and it is now practised by many millions of Pentecostalists. It has recently become an accepted part of mainstream church life in the Church of England because of the success of the Alpha course, based at Holy Trinity Brompton in Knightsbridge. No one who takes the course is expected automatically to burst into ecstatic tongues at services, but the course aims to leave new Christians open to the whole range of religious experience, including the charismatic.