In this Comparative Religion Textbook, Dr. Nkosi Aberdeen provides an Illumination of a Universal Spiritual Core inherent in multiple religious paths, which can be used functionally by (Comparative) Religion Educators and Humanitarians in general, for the development of Peace, Progress, and Prosperity in multi-ethnic, cosmopolitan Societies. In the Book, to achieve this objective, Dr. Nkosi Aberdeen provides key, pertinent, general information and philosophical material from the following Religions: African Traditional Religion, Native American Religion, Hinduism, Buddhism, Taoism, Confucianism, Christianity, Islam, and Rastafarianism. The globalized, multi-ethnic, multi-religious, modern World has become increasingly psychologically & socio-economically stressed. In many cosmopolitan societies, socio-economic tensions amongst groups & classes of people are exacerbated by conflicts caused by the nature of the multi-ethnic and multi-religious composition of modern Society. Religion, as a function, can be used to promote divisions in society; or alternatively, as Dr. Nkosi Aberdeen attests in this Book, Religion (Religious Education-SIAB Pedagogy in particular), can function as a catalyst for the unity and progress of diverse groups of people. In this Book Dr. Nkosi Aberdeen highlights the potential positive role of Religion (Comparative Religion especially) in the reduction of Horizontal Inequality (Inequality amongst groups of People) in contemporary, cosmopolitan, globalized Society.