The Invisible Source of Authority is a philosophical meditation on the secular age and challenges the notion that the secular can be understood without reference to God.

How does one reject God while denying belief? This is the central paradox of our secular age, where efforts to erase God only affirm his presence. In The Invisible Source of Authority, David Walsh examines this paradox and argues that a secular world actually reveals God more clearly, rather than bringing about what has been called the death of God. Unlike many critics of modernity, Walsh argues that secularism is not inhospitable to authentic religious faith and cannot be understood without reference to God.

Drawing on the writings of early modern thinkers like Montaigne, Descartes, and Grotius, Walsh asserts that God's absence from the secular world is testimony to God's transcendence. Because the secular is always that which has withdrawn from serving God, Walsh suggests that this presupposition proves that God remains indispensable to the self-understanding of secular society. The Invisible Source of Authority seeks to remind us that, despite his seeming absence, the transcendent God remains an essential presence.