The Archbishop of Canterbury continued his mission to shift the Church's relationship to finance as he commissioned a group of 'Church Credit Champions' in a service in east London tonight.

The volunteers will help churches tackle issues of debt, credit and money in their local area. Gathering from dioceses across London and Liverpool, they listened to Justin Welby speak of the need to improve the Church's engagement with money.

"Christian relationship with money has been ambivalent at best," Welby said in his sermon. "We know what is wrong but we are unclear what is right.

"The classic response is just to stay out of the system."

Welby hopes this new project will help the Church engage more positively with credit and debt. The former oil executive said money was master and tyrant over so many lives but also spoke of the positive effect it can have.

"It is a shock when money, which promised to look after us so well, proves to be a cruel master," he said.

"But when money is turned in to a servant, it releases what God has given us in creativity.

"Money has to be the protagonist in some stories for that story to work."

The service at St George in-the East Church, Shadwell, also featured testimonies from people who had struggled with debt in their own lives.

"Undoubtedly I made some bad decisions," one woman said.

"But the other side of the story is that there is an industry which makes money of people's misfortune and weakness," she continued, referring to payday lenders.

These outfits offer short-term loans to people struggling for cash but charge extortionate rates of interest, leaving many crippled with burdensome interest rates.

Since their peak, churches have led a campaign to limit the amount payday lenders could charge.

However Welby has admitted that regulation is not enough and in 2013 he announced he wanted to "compete Wonga out of existence." The Church has since thrown its weight behind credit unions as an alternative.

Welby described payday lenders as the opposite of grace because they ask how much can we charge and still survive? By contrast, credit unions ask, how little can we charge and still be sustainable?

Since 2013 when the archbishop's task force on responsible credit and saving was established, the volume of payday lending in the UK has declined by 68 per cent. Membership of credit unions has continued to rapidly grow over the last decade.

Welby called the shift a "move of the Spirit" and said those who were commissioned as credit champions had "responded to the call of God."

Ultimately, he said, the role of the credit champions must be to point to Christ.

"I urge you to point to liberation, to the true value of humanity which is given by God, not money."