In this wild time of fire and sword, the spiritual struggle was carried on more nobly and purely by him than by any one else. Every interference of earthly power was hateful to him; he did not choose to be protected even by his own sovereign, and would not have any human support for his teaching. He fought with a sharp pen, alone against his enemies; the only pile that he lighted was for a paper: he hated the Pope as he did the devil, but he had always preached toleration and Christian forbearance towards papists; he suspected many of having a secret compact with the devil, but he never burnt a witch. In all the Roman Catholic countries the stake was lighted for the confessors of the new faith, and even Hutten was strongly suspected of having cut off the ears of some monks; but so benevolent were Luther's feelings, that he had heartfelt compassion for the humbled Tetzel, and wrote him a consolatory letter. His highest political principle was obedience to the authorities ordained by God, and he never rose in opposition to them except when necessary for the service of God. On his departure from Worms, although on the point of being declared free from interdict, he was forbidden to preach; he did not, however, desist from doing so, but suffered great anxiety lest it should be imputed to him as disobedience. His conception of the unity of the Empire was quite primitive and popular; the reigning princes and electors, according to the laws of the Empire, owed the same obedience to the Emperor that their own subjects did to them.