Mary Stuart was accused of many things, but never of being a theologian. Nevertheless, at the end of the summer of 1561, the recently widowed and star-crossed Queen, in an extraordinary interview with the intrepid Reformer, John Knox, put her finger on what was perhaps the fundamental question of the Reformation. Concerning the respective credentials of the Kirk of Scotland and the Kirk of Rome, she pleaded: ‘Ye interpret the Scriptures in one manner, and they interpret in another. Whom shall I believe? And who shall be judge?’ Knox's reply was, au fond, an appeal to the Holy Spirit.