In November 1750, a young English couple, Thomas and Catherine Armitage, approached the London Moravian congregation for membership. Two years later, the now-widowed Catherine married James Blake, father of the poet. Those few years when Blake's mother worshipped at Fetter Lane coincided with a period of great turmoil in the spiritual life of the Moravian Church. Blake's, like most people's, conception of the past owes less to the work of conventional historical writing than to a host of other, more ubiquitous influences among which family tradition must have played a part. In the Moravian community of the mid-eighteenth century are to be found specific and definable practices, beliefs and customs which all contribute towards suggesting the spiritual milieu with which the young William Blake would have been familiar. It is not just simple curiosity that makes us want to know what sort of relationship he had with his father; how his mother's death affected him; whether he knew his grandparents. We need to know what lives his parents led and what stories they might have told.

What is distinctive about the Moravians is not their theology, not a body of doctrine, which their opponents sought to traduce as heretical and antinomian, but their spirituality, their search for transcendence – a spirituality, in line with the Moravian leader Count Zinzendorf 's Ehereligion (marriage religion), that was Christocentric, focusing on Christ as the husband.