This research is a preamble to working out modalities for religious harmony in the Nigerian society. As a polity, the Nigerian nation-state has experienced religious upheavals that did not augur well for the state and citizenry. This is due to some salient facts, such as the lack of delineation of the appropriate space and boundaries to which the state and religious spheres should interact or interface. Also, the Nigerian state is not employing the religious sphere as an appropriate instrument for social harmony, cohesion, and coherence. Hence, this research work employs and unearths fault lines and fosters relationships through appropriate and relevant high-impact institutions of religious convergence in Nigeria, like: Inter-faith dialogue commissions, ecumenical centres, faith-based organisations and civil society organisations. In understanding the role of religion in Nigerian society, this research employs social conflict theory, liberation theory and globalisation theory to understand better the interface of state and religion(s) in Nigeria. It basically uses secondary sources of data collections, like research writings of relevant authorities on religious harmony in Nigeria, usages of library sources, perusals of feature write-ups / religious magazines, and visits to ecumenical centres/inter-faith dialogue centres for works already done in these topical directions of research. Some end product findings were that the Nigerian State lacks a non-charlatan to regulate the religious spheres for social harmony, cohesion, and coherence. Having the state controlled by religious adherents often brings about conflicts of interest amongst Nigeria's three important adherents (Christianity, Islam, and African Traditional Religion). The Nigerian state has yet to harness and use convergence centres and celebrations for its citizenry's terrestrial and transcendental benefits and tangible socio-economic developments.