Justin Humphreys, Head of Safeguarding at the Churches' Child Protection Advisory Service (CCPAS), said convicted abuses think churches are a "soft touch".
Mr Humphreys also accused churches of being guilty of "naivety" on the issue of sexual abuse: "My research highlights the fact that, far too often, churches are under the impression that all they have to do to ascertain that somebody is safe to work (either in a paid or voluntary capacity) with children or vulnerable adults is to carry out a disclosure check.
"Nothing could be further from the truth. Disclosure checks should be obtained only at the very end of the process, after all the other necessary safer recruitment practices have been completed. So all churches must devise a job description and person specification, advertise each post, take and verify references and any qualifications required and conduct a robust interview.
"My message is that a DBS check, on its own, is simply not insufficient to ensure children's safety because it means that abusers could, potentially, be slipping through the net."
In recent years the Roman Catholic church has been hit by abuse scandals resulting in new rules to protect children.
Two years ago the Church of England issued an apology to victims, but last week it came out that more than 140 allegations involving the Church of England have been made in the last six months.
The Church of England have released a statement:
"We are committed to making our churches a safer place for all and are working to ensure that all we do is informed by the voices and experiences of survivors of abuse.
"Through legislation currently going through General Synod and new guidelines we are striving to improve the consistency of our safeguarding work across parishes and dioceses.
"This includes our response to concerns and allegations, training, and undertaking safer recruitment practices such as DBS checks or risk assessments with those who may present a risk to others.
"We are also increasing our resource within the national safeguarding team to improve our capacity to strengthen our safeguarding arrangements with national policy/guidance, training and quality assurance."
Listen to Justin Humphreys speaking on Premier's News Hour here: