Atheists have hit back at criticism by religious leaders, claiming the clergy have made non-believers a scapegoat for declining church congregations.

Several church leaders have used their Easter sermons and messages to condemn the increase in atheism, with Sydney Anglican Archbishop Peter Jensen on Friday describing non-belief as an "assault on God".

Bishop Anthony Fisher.

His comments come a day after Sydney Catholic Archbishop Cardinal George Pell also criticised non-believers.

The Atheist Foundation of Australia said on Friday Dr Jensen's claims were "preposterous" and condemned Christianity for a spate of child sex abuse scandals.