Here are some thoughts on the nature and validity of faith by Wolfhart Pannenberg.
I found these in Systematic Theology, Volume 3. (There is no Kindle edition for that yet — sorry to say.)
Faith is a form of the way we relate to truth, and is comparable in this regard to knowledge. In Hebrew the terms for “truth” (’emet) and “faith” (he’emin) are linguistically related, deriving from the same root. Truth in the sense of ’emet is what is constant and therefore trustworthy, so that we can build on it. He’emin denotes the confidence that establishes itself on the basis of that which is constant, so that those who have it achieve steadfastness and constancy. But only God and his Word and works are fully stable and trustworthy (Ps. 111:7-8; 119:90-91; 146:6; etc.). Hence, those who would be firmly established themselves must be established in God.
— Wolfhart Pannenberg, Systematic Theology, Volume 3 trans. Geoffrey W. Bromiley. Eerdmans, Grand Rapids, 1998. page 136.
Faith … is not just acquiring information or assenting to a doctrine. The decisive thing is the relation of faith to time, to the future that God will bring, and therefore to God himself.
— page 138.
The Reformers constantly set faith as trust in God’s promise in opposition to an understanding of faith as mere knowledge of something that one may have at a distance and without personal involvement.
— page 142.
It is worth noting that saving faith does not in any way rule out historical knowledge as its antithesis, in contrast to many modern interpretations. The point instead is that mere historical knowledge by itself is inadequate precisely because it fails to grasp the deeper meaning of the history, its bearing on our salvation and therefore on each of us personally.
— page 143.
In knowledge of the history of Jesus, and in assent to the Church’s message in imparting this knowledge that God is revealed in the facts linked to the identity of the person of Jesus, we do not primarily have psychological motives for faith but logical conditions for believing that faith’s trust in the God revealed in Jesus Christ has a good material basis.
— page 150.
A supreme feature of the integrity of faith is that it does not live of itself but by the given reality of God and his revelation in the history of Israel and its eschatological fulfillment in Jesus of Nazareth.
— page 153.
The nature of faith is to rely on God as other than itself and thus to have the basis of its existence outside itself. Only so long as the reality of God and his historical revelation unequivocally precedes the subjectivity of faith can believers be certain that they trust in God and not in themselves.
— page 153.
I think this point of view on faith is similar to the perspective that Pascal had, that is: faith as a precondition to scientific and mathematical knowledge.
We can claim to “know” precisely because we have “faith” that there is a stable and secure (trust-able) reality outside our minds. Christians believe this on the basis of the God that we know through Jesus Christ.