I think religion is a drug. Can God deliver a religion addict? (laughs)
This is not a Marx quote. These are the words of Marjoe, in his biographical documentary film which I learned about from youtuber gogreen18 -a brilliant atheist and ex-Mormon-, tells the story of a child who was raised to be a preacher and began preaching at age 4. In it, he speaks of his career as a preacher, and of religion as a business ... and is frank about his personal lack of belief.
The documentary is from 1972 and served as his coming out atheist story and his chance to break with his religious past.
The film is a great focal point for discussion with church goers, particularly when arguing against tax exemptions for religious organizations that provide no real non-profit services except the false promises and false hopes of faith. It includes cheerful counting of huge amounts of money after a service, as well as conversations about a pastor's family's trips to Brasil, and even land owned and being used for profit in foreign lands - presumably purchased with church money. In it, he explains how easy it is to manipulate people of faith and to make money from a church business. Very educational!