The English regicides who tried and condemned their reigning monarch as a “tyrant,” “traitor,” “murderer,” and “public enemy” could not have chosen a worse day than January 30, 1649 for his public execution. Whether by unlucky coincidence or divine providence, the second lesson appointed for that day in the Book of Common Prayer was the 27th chapter of Matthew's Gospel, on the trial and crucifixion of Christ. According to the royalists, the biblical narrative inevitably shaped the observer's understanding of the execution: “we could not but conceive, that the murther then to be acted, was like unto that which in the chapter is described.” Speaking from the scaffold, Charles encouraged this comparison; he forgave his accusers and declared himself “the martyr of the people” (Trial, pp. 141–2). Although the regicides could cut off the king's scaffold performance with one blow of the executioner's axe, the myth of the execution as the crucifixion reenacted proved much more durable. The spectacle of Charles I's Christlike martyrdom lived on in the most successful piece of royalist propaganda to issue from the English Civil Wars: the Eikon Basilike, commonly known as the “King's Book.”

In the Eikon Basilike, Charles does not merely claim a divine right to rule, but also a more personal kind of divinity: he strives “to imitate [his] crucified Redeemer” in “suffering for righteousness' sake” (EB, pp. 157;176).