Laudatur Iesus Christus.
“[The] Church has always considered the act of entrusting oneself to God to be a moment of fundamental decision which engages the whole person. In that act, the intellect and the will display their spiritual nature, enabling the subject to act in a way which realizes personal freedom to the full. It is not just that freedom is part of the act of faith: it is absolutely required.” (John Paul II, Fides et Ratio 13)
The “fundamental decision” and “personal freedom” mentioned in the above quote from John Paul II seem at odds with your description of belief as passive. Certainly, a belief based on will alone, without reason, does not engage the whole person, and is not how God wishes men to believe: He works too many miracles as proof of His Divinity for that to be the case. I suggest that there is another theory of belief that includes both reason and choice.
In the Profession of Faith said at every Mass, the Church says “I believe in One God”, in Latin, “credo in unum deum.” The Latin word “credo,” related to the English word “credit” was used originally in business, meaning, “I give a loan.” When a person makes a loan, he entrusts his own things to another person, with the expectation of a good return. Thus, credo is what we’re willing to risk acting on.
When a person believes (credits) someone else, he does the same thing. If my car is having problems, and I bring it to a friend who is good with cars, I entrust my car to my friend with the expectation of good results. If he tells me to let the car run for five minutes every time I start it, then I either take his advice and entrust that small piece of my actions to him, or not. Either credo or non credo. I act based on my trust in the person, not because I, myself, understand why it works.
There is a further point that ought to be made about belief in Christ and His Church. When we trust that the Church is divine, on the reasonable basis of Christ’s promises, and the Church’s enduring goodness and unity and miraculous power, we admit that she has more foresight and knowledge than we do. Thus, when Mother Church proposes something for belief, we act on what she proposes, not because the belief itself is something we understand, but because she is credible. We do the same as children of Mother Church that we did as children of our earthly mothers – trust her judgments even when we don’t understand them.
On this theory of belief as credit, belief is a thing that is taken up actively, on the basis of the credibility of the person believed, not on one’s own understanding of the thing to be believed.
Pax Christi nobiscum.