John Knox’s “purgation” or letter of apology to Elizabeth I for the views he put forth against female sovereignty in The First Blast of the Trumpet against the Monstrous Regiment of Women has been known to scholars for some time, and was included in collections of Knox’s complete works.Less known, and apparently unpublished, is an annotated version of this letter that sets out the Elizabethan establishment’s objections to Knox’s views on regnant queens and in particular to his repeated argument that Elizabeth I was only permitted to reign through a divine “special dispensation.” This article provides, as an appendix, the full text of the annotated version of Knox’s letter.It argues that Knox’s views were alarming to the English government as a whole, not just offensive to Elizabeth personally, and that Knox’s apparent refusal to retract his views stems from his own self-image as prophet.