The Archbishop of York, Dr John Sentamu, called for the Church to resist "rhetoric" that accuses people of choosing a life of idle dependence on the welfare state.
"It is an insult to claim that poverty in this country is caused by people choosing unemployment," he told members of the General Synod. "Six out of 10 families in poverty have at least one adult in work."
Dr Sentamu continued: "We need to remember who caused our economic downturn. Was it those workers on low wages, working hard to provide for their families - or was it the gambling casino culture of a group of wealthy bankers that has left our economy where it is today? Who was bailed out with large sums of money?"
The Rt Rev John Packer, Bishop of Ripon and Leeds, said: "The vast majority of those receiving benefits need them to live appropriately in our society and we should not be deflected from that purpose by stories of an easy ride on benefits."
He said the tax was based on "false assumptions" - of a flow of suitable housing, that family life is stable, that "anyone can move without trauma" and that jobs are available.
"Already there is a massive build up of rent arrears, the local council can currently assist with transition funding but won't be able to do so next year. Already rent arrears are up 22% in the last three months," he said.
"In this build up of arrears, in the removal of people from their networks of support, in the cultivation of a climate in which the poor are increasingly blamed for their poverty, a time bomb is ticking."
The bishops were speaking during a debate on welfare reform and the Church. The Church's national assembly, meeting at York University, backed a motion calling for "close attention" to the impact of welfare cuts on the most vulnerable.