In 1839 a diverse group of Hindu leaders began gathering in Calcutta to share and propagate their faith in a non-idolatrous form of worship. The group, known as the Tattvabodhini Sabha, met weekly to worship and hear discourses from members on the virtues of a rational and morally responsible mode of worship. They called upon ancient sources of Hindu spirituality to guide them in developing a form of modern theism they referred to as "Vedanta." In...