To ensure that people should have good feelings is extremely desirable, but it cannot be achieved by preaching. On the contrary, one of the effects of a belief in sin is to justify malevolence towards the sinner under the guise of a wish to bring him to repentance. When we get rid of the belief in sin, it becomes much harder to disguise our unkind feelings, under a cloak of morality
Source:Mortals and Others; Bertrand Russell's American Essays, 1931-1935, v.1.
More info.:http://russell-j.com/EDIFY.HTM