Marx believed that in this kind of system, the laborers are oppressed. They work a lot and yet they get very little. On the contrary, the capitalist hardly works at all and yet they get almost everything. And it is in these circumstances that Marx made the aforementioned statements.
Due to oppression, people needed something to believe in. They feel weak and powerless against the system. They believe that there is nothing they can do. That change is beyond their power. And because of this desperation, the people needed to believe that there is a higher power. They need to believe, even if they don't understand why the system is so unfair, that all this is part of a greater plan. That someday, they will be at ease. They need to believe that someone out there is aware and sympathetic of their misery. That someone out there would give them comfort. Thru religion, the oppressed find hope.
As such, Marx believed that religion is a response to oppression. This is the reason why he said that religion is "The sentiment of a heartless world, and the soul of soulless conditions." Without a 'heartless world' or 'soulless condition', religion would not emerge. If people where truly satisfied with the current state of things, they would not look for other places for happiness. They would not turn to religion of hope and comfort.
In this context, Marx also said "Religion is the sigh of the oppressed cre...
Hence, to believe in a certain religion is the only thing that the oppressed can do to make them feel better.
"It is the opium of the people" Marx said. And we all know that opium is a narcotic drug. And we are aware what narcotic drugs can do. They provide an illusion of happiness, a fantasy. They make you feel better without solving the problem. To Marx, this is what religion provides to the people. The happiness that religion provides is not real, only momentary and most importantly, it does not solve the problem of oppression.
Since religion provides happiness and hope to the people, for the meantime, they are contented. This prevents them from seeing the situation for what it really is. Instead of questioning the system, their attention is diverted to religion.
Because of this, Marx also believed that the capitalist actually uses religion to pacify the people and maintain the system. I think the capitalist are aware of how significant the laborers' contribution is to the whole production. And without laborer cooperation, the whole economic system will fall. So the capitalist encourage the development of religion to keep laborers happy. And if they are happy, they continue to work for the system. They don't realize that the system is actually unfair to them. They are actually being oppressed by this system.
Second Part: Explain why the socialization of means of production would eliminate the need for religion.
In a capitalist system, the capitalist owns the machineries and materials which the laborers use for production. As a result, bulk of the profit goes back to the capitalist.
If there is a socialization of means of production, said machineries and materials would be owned by the people themselves. In turn, the