This article examines Pope Francis's understanding of the relationship between church and state, the ends of civil authority, and the importance of religious liberty. It argues that Francis challenges claims made by legal and religious scholars that civil authority must be neutral as to religious ends. Francis, the article contends, uses the categories of idolatry and solidarity as opposing ends that are cultivated by civil authorities caring for, most notably, the economy and the environment. Both are religious. Idolatry is the solipsistic pursuit of created things as an ultimate end and solidarity entails living in communion with God and others. The article further considers how these arguments have shaped Francis's views on religious liberty. Francis points to the importance of civil authorities respecting conscientious objection, the desirability of cultivating healthy pluralism, and religious liberty as securing the end of solidarity. This presents two challenges: first, to recent legal scholarship questioning the special importance of religious liberty; and second, to the exercise of religious liberty itself. If religious liberty is protected for the end of solidarity, can it be exercised wrongly? The article concludes by considering the Supreme Court's 2014 Hobby Lobby decision.