The Church of England has an "almost supernatural gift" for presenting itself in the worst possible light in the eyes of the public, the Archbishop of Canterbury has said.
Dr Rowan Williams said the public needed to know about the "good news" of Christian belief manifested in the work of groups such as the Church Urban Fund and the Church's response to events such as last summer's riots.
"It is sometimes said that as a Church we sell ourselves short," he said in a sermon at a service in St Paul's Cathedral to mark 25 years of the Church Urban Fund.
"We certainly have an almost supernatural gift as the Church of England for presenting ourselves in the worst possible light in the public eye."
He added: "One of the great challenges of the last nine months or so has been to try and get hold of what the Church was actually doing last summer at the time of the riots and hold it up before a public which is largely ignorant of this.
"But that is only one of many, many examples.
"We need to know and our society needs to know that there is good news about what the love of believers can achieve."
The Church Urban Fund, which supports more than 300 Church and Christian projects tackling poverty, is helping society see the reality of powerlessness and deprivation - a reality which most would prefer not to see, Dr Williams said.
His remarks come after the Church was attacked by gay rights campaigners last week over its criticism of government plans to introduce same sex marriage. The Church also faces more argument over the introduction of women bishops at the General Synod of the Church of England next month.
Dr Williams told the Evening Standard in an interview that Britain was "haunted by Christianity".
He said: "There's a bit of can't live with it, can't live without it in some people's approaches.
"Even with (Richard) Dawkins, the sense that he can't leave it alone is fascinating."