This is the first published edition of a fascinating manuscript on witchcraft in the collection of the British Library, written by an unknown sixteenth-century scholar. Responding to a pre-publication draft of Reginald Scot's sceptical Discoverie of Witchcraft (1584), the treatise represents the most detailed defence of witchcraft belief to be written in the early modern period in England. It highlights in detail the scriptural and theological justifications for a belief in witches, covering ground that may well have been considered too sensitive for print publications and presenting learned arguments not found in any other contemporary English work. Consequently, it offers a unique insight into elite witchcraft belief dating from the very beginning of the English witchcraft debate. This edition, which includes a comprehensive analytical introduction, presents the treatise with modernised spelling and relevant excerpts from Scot's book.