A quote from Catholic historian Christopher Dawson (1889-1970) in “Religion and the Modern State” (1936):
Religion gradually retreated into man’s inner life, and left social and economic life to the State and to a civilization which grew steadily more secularized. A man’s debt to religion was paid by an hour or two in church on Sundays, and the rest of the week was devoted to the real business of life — above all, the making of money. Such a division of life into two compartments — and very unequal ones at that — was not the Christian solution, nor could it be permanently successful. If religion loses its hold on social life, it eventually loses its hold on life altogether. And this is what happened in the case of modern Europe. The new secularized civilization is not content to dominate the outer world and to leave man’s inner life to religion; it claims the whole man.
The Christian tradition contains an infinite depth of spiritual resources, but these possibilities can only be realized and actualized in a Christian culture by the dynamic activity of individual Christians. The supreme example of this vital religious action is to be seen in the saints, in whom alone the potentialities of Christianity are fully realized. And their action is not limited, as we sometimes suppose, to the sphere of their supernatural virtues, it flows out into the world and shows itself in social activity and intellectual culture.
Whenever Christians cease to be active, when they rest in a passive acquiescence in what they have received, Christianity tends to lose contact with contemporary culture and the world drifts away from the Church.