In a message for churches taking part in Back to Church Sunday, Dr Rowan Williams said: “The desire for God is undimmed in Britain. This country has not turned its back on God or spiritual things.
“And the Church of England is here for the whole nation: we are a spiritual home on every street corner.
“Many more people would come if they knew they were invited, so I’m inviting you.”
Churches across the UK are expecting larger numbers than usual at their services on Back to Church Sunday today.
Thousands of churches across the denominations are taking part in the annual initiative, which has seen churchgoers hand out around 400,000 invitations to friends and neighbours in the last few weeks.
Back to Church Sunday has been accompanied by a radio campaign, with a short advertisement airing on Classic FM and Heart FM in which churchgoers say what church means to them. The advertisement was broadcast three times a day and heard by an estimated 1.3 million people.
The Back to Church Sunday was first launched in the Anglican Diocese of Manchester in 2004 but has since been rolled out to all 44 dioceses in the Church of England. Other Church denominations have since got onboard, including the Baptist, United Reformed and Methodist Churches and The Salvation Army.
This is the first year that the Baptist Union of Great Britain has issued resources specifically tailored for Baptist churches.
The Baptist Union has rebranded the initiative ‘The Big Welcome’ and more than 400 of its churches are participating this year.
BUGB Head of Mission, the Rev Ian Bunce, said the response to the new materials had been positive.
"There has been some very warm, positive feedback, that the resources reflect the Baptist identity that bit better," he said.
"People have appreciated that it’s not about church, but a welcome; that they’re not tied to ‘back’ so people feel happier about inviting people who have never been to church; and that it doesn’t mention Sunday – some churches are hosting other events, like my own, which is having a harvest supper.
"These things had become an issue for some churches. They said it didn’t fit them. These new resources give them that flexibility."