Constantine did not require all Romans to adopt Christianity (given that Christians were still a minority, this would have been too radical a measure for the time) but his sponsorship, in Lactantius' eyes, and his own, personal faith was seen as evidence that God himself had blotted out the bad emperors who had killed Christians and taken their land -- the land subsequently restored by Constantine. During the 10th century, however, a far less sanguine view of the influence of religion in politics was articulated in Gregory VII's Dictatus Papae (323) and Henry IV's "Letter to Hildebrand" (323-324). In these documents, the two leaders are clearly fighting for political power. The Holy Roman King Henry IV was struggling to retain the ability of secular authorities to have direct influence over church appointments. The Roman Emperor had previously had tremendous power over every facet of medieval life -- powers the Church was attempting to encroach upon. He wrote angrily to the Pope: "Thou hast won favour from the common herd by crushing them; thou hast looked upon all of them as knowing nothing, upon thy sole self, moreover, as knowing all things." Henry criticized what he saw as Gregory's self-interested meddling in politics. When Henry wrote his letter, Christians no longer believed that the kingdom of heaven was nigh and being enacted upon the earth in the personas of the Pope and the Emperor. Instead, Henry was struggling to create a functional state in the midst of chaos, and also to shore up his own power.

Articulated in Henry IV's words is the clear sense that there is a conflict between religion and politics. Instead of being harmonious, Henry creates a dichotomy between the two. He criticizes the Pope of hypocrisy in using force and the seat of faith to serve the Church's own needs: "By wiles, namely, which the profession of monk abhors, thou has achieved money; by money, favour; by the sword, the throne of peace. And from the throne of peace thou hast disturbed peace, inasmuch...

This was of great importance, given the power of these positions at the time.
In our own, secular understanding of the world, it might be tempting to sympathize more with the Pope in this instance, then with Henry, given that Gregory's assertion of church rights concerned sacred, rather than secular offices. The conflict between the two men illustrates the difficulties of having state and religious authorities have so much interrelated power. Gregory had already angered Henry by asserting the right of the College of Cardinals, not the emperor, to appoint the pope and the Investiture Controversy further depleted Henry's office of owner.

Gregory VII's Dictatus Papae, or declaration of the Church's rights vs. those of secular authorizes, was to have a lasting influence upon the relationship between the Roman Catholic Church and European kings. The church asserted its exclusive rights to appoint officials as distinct from that of the state. It also confirmed the moral authority of the Pope, stating that "Roman pontiff alone can with right be called universal" (in contrast to the Emperor) and "That he who is not at peace with the Roman church shall not be considered catholic." Even after the specifics of the Investiture Controversy were resolved later in the Concordat of Worms, the question of when the Pope could meddle in secular affairs vs. The right of kings to ignore the Pope would rage on.