This paper explores the socio-economic world of the Manichaean-Christians associated with the Roman village of Kellis during the fourth century AD. It discusses the role played by the ownership and exchange of property (e.g.money, clothing, medicine, books etc.) in defining the kinship relations between the correspondents, whose letters comprise the archive of documentary texts recovered from Kellis (edd. I. Gardner, A. Alcock, W.-P. Funk (Oxford, 1999)). The paper analyses the correspondence in light of recent trends in late antique religious and economic scholarship (e.g. the popular treatment of Gift Exchange in the work of Charles Eisenstein (Sacred Economics(2011)), and dissects the triangulation of familial, religious, and business concerns which lie at the heart of the Kellis archive. The paper reveals the ways in which the documentary archive yields important evidence for rethinking ideas about religious identities in late antique Egypt, and its finding will be used to argue for a revision of the current taxonomies applied to the study of late antique Manichaeism. The paper demonstrates how fundamental issues in evidence in the archive – e.g. familial and gender roles – were shaped by the religious and economic concerns of Kellis’ Manichaean-Christians. The paper concludes by arguing for closer integration of the archive, which relay the quotidian and economic concerns of the religion as practised by its Roman-Egyptian adherents, into the historical study of the theology and ecclesia of late antique Manichaeism.