Faith
Knowledge of God given by revelation is grasped by faith. Despite Protestant suspicion of Catholicism, the Protestant theologians who developed the Reformation idea that we are saved by faith borrowed language for talking about the complexity of faith. They used Latin words to distinguish different things the word “faith” can refer to.
Notitia. Think of the English word “notion.” Notitia is faith as a conceptual matter. What are the ideas of the faith? For instance, you might answer this question with a list of topics (belief in God, belief that Jesus died to save lost human beings, belief in justification by faith). This is content of faith that can be known (even by people who are not Christian). Someone who is not Christian could do well on a religious studies exam question about Christianity by articulating the content of “Christian faith.”
Assensus: Think of the English word “assent.” This goes beyond knowing mere content to assenting to this content. A person writing the correct answer on an exam might be able to state the content without believing it. The assensus aspect of faith indicates acceptance of (assent to) what is to be believed.
Fiducia: Think of the word “fiduciary.” This goes beyond content and belief to trust and confidence. Think of the way you may trust a person or persons to handle money or operations. Trust adds something to content and even to assent. With this aspect of faith, you are letting your life be guided and shaped by the God you trust.
Notitia and assensus are about the “what” of faith. Fiducia is the “how,” the way you respond to what you know of God and what God is doing. For the Protestant theologians who borrowed these distinctions, faith was really “saving” when it was fiducia. “Saving” will be unpacked more in an upcoming article about salvation, but for now the important point to grasp is that faith becomes effective in your life to enable your response to God. Some have expressed this as moving from head to heart.
John Wesley, the founding theologian of my tradition (United Methodist), did not explicitly use these categories. He did, though, frequently make the point that when we are saved by faith, we are not saved by right ideas but rather by our trust. He sometimes says (as the older Protestant theologians did) “even the devils believe,” (from James 2: 19), meaning the devils know everything about the content of Christian faith, and they know it to be true. But they do not trust in it. Saving faith is not speculation (forming ideas) but rather a disposition of the heart. It is living your life in “sure trust and confidence” of God’s love. He referred to faith as “recumbency” a word we rarely use these days, but which calls to mind a resting posture like reclining or leaning. A life of faith rests confidently in God. Faith that rests in God’s love truly grasps the self-disclosure (revelation) of God.
To say faith is not speculation does not mean ideas are unimportant. The ideas we use to express our faith do matter because what we think about God will surely affect how we relate to God (hence the need for theological reflection). Exclusive focus on ideas, though, may distract us from relationship.
One of my teachers spoke of faith as accepting God’s acceptance of us. Justification is being made right with God by God’s loving forgiveness. This is God’s acceptance of us. Our faith response is to accept that we are loved, to trust in this love, and this trust sets us free, that is, allows us to live differently in response to that love (see Schubert Ogden,The Understanding of Christian Faith).
Saving faith, then, is not understanding or even accepting as true a list of “beliefs.” Saving faith is a disposition of the heart that responds to God. It is trust and confidence in God’s love for us that brings us into relationship and allows us to be shaped by that relationship. For Christians, Jesus shows us what that kind of life looks like. We learn from him how to see ourselves as well as how to think about and respond to others.

Fascinating, as usual. I value your posts enormously. I have definitely been guilty of concentrating on the notitia in the past. In fact, I’ve never really passed beyond that, because although an initial, naïve understanding of Christianity is full of supernatural elements which we are assured led to supreme faith of the companions of Jesus, this fiducia cannot withstand deeper study. Ultimately assensus and fiducia are victims of notitia. In my case, anyway.
Having been a lay minister for decades this gives me a vocabulary for something I hold dear; thank you