41 He yielded no ground on any matter that would endanger faith and morals. He admitted no claim (even if it was made by a powerful monarch who was always a Catholic) that was either contrary to discipline or burdensome to the faithful. He was always mindful of Christ's words: "Render...to Caesar the things that are Caesar's, and to God the things that are God's." He never forgot the Apostles' declaration: "We must obey God rather than men." Thus he was religion's and society's chief benefactor. In his time civil society was paying the price of almost certain destruction because of its worldly prudence. It was practically shipwrecked in the seditious storms it had stirred up.
Source: Editae Saepe (Vatican.va)