The document discusses the relationship between religion and nationalism. It begins by defining religion as a unified system of beliefs and practices related to sacred things. It then examines how religion can be a source of division or help form national identity. Religion often impacts society through effects on education, language, rituals, and politics. Religious affiliation is sometimes linked to national identity, as seen in examples from Northern Ireland, Sri Lanka, and the former Yugoslavia. Overall, religion can both unite multiple nations under one faith or divide a single nation among different faiths.