This chapter traces the religious aspects of Lord Stanley’s probation system and its impact on the anti-transportation campaign. After examining regulations devised for Pentonville, which established the probation system and connected it to reform in the penal colonies, it considers the staffing and implementation of probation’s religious provisions by the new class of religious prison officers, many of them pious laymen attracted to the system’s reformative principles (and the relatively generous salaries). The system’s ultimate failure provided powerful ammunition for the closure of penal colonies and fuelled the emergence of a settler lobby demanding an end to all transportation. The campaign would take almost twenty years to succeed and involved an extraordinary effort to bring religion to the dark places of the penal system: on board the ‘floating hell’ of the hulks and transports and in places of secondary punishment, from the ‘hell on earth’ of Port Arthur to the ‘ocean hell’ of Norfolk Island, and the naval dockyards of Bermuda and Gibraltar. It all began with Pentonville.