What are the motifs in A Connecticut Yankee In King Arthur's Court by Mark Twain?

Religion is a recurring idea in the book. In just one of the many places in the novel where he rails against the Roman Catholic Church's corrosive influence on society, Twain's narrator notes that, "In two or three little centuries it had converted a nation of men to a nation of worms. Before the day of the Church's supremacy in the world, men were men, and held their heads up, and had a man's pride and spirit and independence." Twain's rage is not confined to just the Catholic Church but also applies to any established church, which he sees as an instrument for suppressing the rights of people by taking their inherent power away from them, making them slaves to the whims of the powerful people who claim to speak for God.