Karl Marx argued that the ruling ideas of each age have always been the ideas of the ruling class.
The dominant religion of a society is that of the dominant class. Marxist scholars emphasised that the role of religion was to justify the political status. It was done-by cloaking political authority making opposition to it seem immoral Marx said. “Man makes religion, religion does not make man”.
He referred to religion as the opium of the masses. He believed that through religion the masses were kept from actions that might change their relationship with the ruling class.
The masses were given the idea that if they followed the rules established by religion they would receive their reward in heaven. So they had no reason to try changes or improve their condition.
Religion is an agency of social control and it imparts a sacred quality. It provides courage for survival. It forms the basic of the unifying principles of every society.