Why was Stalin against organized religion?

Stalin was against organized religion primarily because he viewed it as a threat to the authority of the state and the communist ideology. He believed that religion promoted superstition and diverted people's loyalty away from the party and the state. Additionally, organized religion often held significant social and political influence, which Stalin sought to eliminate to consolidate his power and promote a secular, atheistic society aligned with Marxist principles. This led to widespread persecution of religious groups during his regime.