Artificial Intelligence (AI) is increasingly becoming part of religious education, communication, research and everyday faith practices. Believers can now use generative AI to explain sacred texts, compare interpretations, prepare devotional materials and seek answers to religious questions without first consulting a recognised religious leader. This development raises an important question for Nigeria: how is religious authority changing when access to religious information is no longer controlled mainly by clergy, scholars and religious institutions? This paper examines the relationship between AI and religious authority in Nigeria, focusing on religious knowledge, leadership and trust. Using a conceptual and interpretive methodology, it synthesises scholarship on religious authority, digital religion, AI ethics and Nigerian religious experience. It argues that AI is not simply replacing religious authorities; rather, it is reconfiguring the conditions under which authority is produced, accessed, evaluated and trusted. Nigerian digital-religion research shows that digital infrastructures can create new forms of religious influence and authority, while recent AI scholarship highlights concerns about accuracy, privacy, bias and human accountability. The paper proposes a Responsible Religious AI Engagement Framework based on human accountability, verification, contextual sensitivity, confidentiality and formation. It concludes that Nigerian religious institutions should neither reject AI nor surrender religious judgment to it. AI should remain an assistive instrument while theological discernment, pastoral responsibility, communal recognition and human dignity remain central to religious leadership.