Faith = firm belief in something for which there is no proofThat's a definition he says he got from Webster's. Well, certainly not from THE Webster's, the one written by Webster himself, here from the 1828 edition:
FAITH, n. ...1. Belief; the assent of the mind to the truth of what is declared by another, resting on his authority and veracity, without other evidence; the judgment that what another states or testifies is the truth. I have strong faith or no faith in the testimony of a witness, or in what a historian narrates.
2. The assent of the mind to the truth of a proposition advanced by another; belief, or probable evidence of any kind.
3. In theology, the assent of the mind or understanding to the truth of what God has revealed. Simple belief of the scriptures, of the being and perfections of God, and of the existence, character and doctrines of Christ, founded on the testimony of the sacred writers, is called historical or speculative faith; a faith little distinguished from the belief of the existence and achievements of Alexander or of Cesar.
The EvC-favored definition makes it appear that there are no grounds whatever for putting faith in anything, it's a totally irrational process.
But it's not necessarily irrational to be persuaded to belief in something by someone who impresses you as credible and trustworthy and that's how most of us come to faith in Christ and in Biblical revelation. As Webster says in his last sentence, this is like believing in the reality of any historical person: you trust the written witnesses to their existence.
We don't believe because of the credibility of the story, which has just about zero credibility in and of itself. God in human flesh? Virgin birth? Miraculous healings? The parting of the Red Sea? Appearances of angels? The resurrection from the dead? Hardly. You have to have been a witness yourself to such things to believe them or you have to find those who did witness such things believable.
Some have excluded themselves from belief in the Bible because of a prejudice against the supernatural on the one hand, and an irrational belief in evolution on the other, deluded that they have "proof" though it's no less mere persuasion by what they regard as credible witnesses than belief in the Bible is.