'Luther, vol. 4 of 6 ' by Hartmann Grisar is a historical account written in the early 20th century. This volume continues the detailed exploration of Martin Luther's life, focusing on his theological perspectives and their implications during the Reformation, particularly his interactions with prominent figures like Henry VIII and the Landgrave Philip of Hesse. The narrative delves into contentious issues such as the acceptance of bigamy and the moral dilemmas faced by Luther and his contemporaries. The opening of this volume introduces a significant chapter discussing "Princely Marriages," specifically Luther's advice to King Henry VIII regarding bigamy in the context of his troubled marriage to Catherine of Aragon. It highlights Luther's hesitance to endorse outright divorce despite his suggestion that Henry could consider polygamy as a solution. Following this, the narrative shifts to the moral quandary of Landgrave Philip of Hesse seeking to take a second wife, revealing the pressures and justifications surrounding Luther's theological positions. This sets the stage for a broader discussion about the practical and moral implications of Luther's teachings amid the shifting landscape of Protestant reform.