This chapter shows that Puritan ministers employed blood guilt as a weapon in the war. In other words, they demanded that all the innocent blood that had been shed during the conflict was to be washed away with the blood of the guilty. According to them, only then God’s wrath would be appeased. This bloodthirsty task of executing judgement was laid on the shoulders of Parliamentarian soldiers: their godly duty was to punish the malignants by killing them if necessary. Hence, religious rhetoric was used not only to dehumanise the Royalists but also to issue explicit commands to kill them. Thus blood guilt, long recognised to be one of the main accusations towards Charles in his trial, should also be seen as a tool for war, employed by Puritan preachers to prepare Parliamentarian soldiers to fight not only the Civil War but also the battle between God and the Devil.