In his book Introduction to Christianity, Joseph Ratzinger writes this:
For to believe as a Christian means in fact entrusting oneself to the meaning that upholds me and the world; taking it as the firm ground on which I stand fearlessly. Using rather more traditional language, we could say that to believe as a Christian means understanding our existence as a response to the word, the logos, that upholds and maintains all things. It means affirming that the meaning we do not make but can only receive is already granted to us, so that we have only to take it and entrust ourselves to it...And further: Christian belief means opting for the view that what cannot be seen is more real than what can been seen. It is an avowal of the primacy of the invisible as the truly real, which upholds us and hence enables us to face the visible with calm composure--knowing that we are responsible before the invisible as the true ground of things.
Christian belief means "entrusting oneself to the meaning that upholds me and the world." That is to say, belief involves accepting the truth that 1) meaning exists, and that 2) this meaning exists prior to me and the world. We do not create meaning, not in any durable, permanent sense. Meaning is something we receive or, rather, perceive. And having once perceived it, we make this meaning the ground and foundation of our being. We become "responsible" before it.
This is how faith differs from materialism. Faith assumes the "primacy of the invisible." What is most true--meaning--is invisible. Materialism, by contrast, assumes the primacy of the visible, observable, and scientific.
And if I could add anything to Ratzinger's account, I'd add in value. The primacy of the invisible means the ontological primacy of meaning and value.
Framed this way, the contrast between faith and materialism concerns the ontological status of meaning and value. Is the cosmos suffused with meaning and value? Or is the cosmos an existential void? Does the universe speak? Or is it mute?
Christian faith confesses the logos, the ontology of meaning.
