Religious believers are more than likely believers in free market fairy tales and capitalism. Religious people are conservatives. Collectivisation and wealth distribution is proportionately based on how much the individuals contribute towards society: individual opportunism.
Socialists are more than likely atheists. Socialists are liberals. Marxists reject God and religion because individualism and selfishness interferes with working together for the state and all members of society. Collectivisation and wealth distribution is based on equal distribution regardless of how much the individuals contribute towards society. The socialist egalitarian utopian dream.
Atheists reject God and religion. Science is God. Atheists believe everything in the world has a scientific and logical explanation behind it. Science can be used to explain most things in our world.
I personally reject religion. Science and logic can explain most things in the universe. I believe there is no big invisible guy in the sky who controls the universe. Science is God.