Knowing by Faith


Faith is a mode of knowing, one that is not contrary to human reason.

Natural Faith

Faith is a mode of knowing, one that is not contrary to human reason. In fact, most of what we do every day is based on faith, and it isn't difficult to show the reasonableness of such faith. The "faith" I refer to here is natural faith, which involves accepting as true something somebody tells you because you have evidence that the speaker is well informed about the subject and is honest. It would be contrary to reason, in fact completely irrational, to refuse to live on the plane of this natural faith.  One could argue that it is impossible.  For example, a child brushes his teeth. Why? Because his mother told him that it is good for him to do so. He doesn't understand why; for he does not understand the concept of tooth decay or the effects of sugar on tooth enamel. And although brushing teeth is not pleasant to him, he trusts her nevertheless. Eventually, when he is able to finally understand, he will see that it was wise to do so.

More than once in our lives will we take a prescription to the pharmacist; he or she will fill the prescription and we will take those pills. Unless we understand chemistry or the intricacies of pharmacology, we don't understand what we are taking. But we trust that the pharmacist did not make a mistake, and we trust that our doctor has our best interests in mind and that what he prescribes to us is really good for us. But we do not know that with any certainty. I once visited a man in hospital who suffered a stroke because his pharmacist made a mistake and ended up giving him pills 10 or 20 times the dosage that his doctor prescribed. He'd spent a year in a hospital bed, his mind was deteriorating, and he was dying.  I'm sure he's dead by now, but there's the trust – had he known, he would not have taken the pills.  But was it unreasonable for him to entrust himself to his pharmicist?  Not at all.

I take my car in for a brake replacement. I am told that it is done, that the car will stop when I press the brake pedal at an intersection. I trust him; I don't really know. I don't demand that he hoist the car up, remove the tires and show me. I trust him.

My students place a great deal of trust in me as their teacher. I teach them all sorts of things about the history of philosophy and religion, but they don't know whether or not  what I'm teaching them is actually true. I could be making it up, all or part of it. They don't know, but they choose to believe me. A responsible teacher will devote a great deal of time and effort to making sure, as far as possible, that what is being taught is accurate, but even that effort involves a great deal of faith.  For example, I put my faith in certain historians of philosophy; I trust Gilson, Copleston, and a few others, but I don't trust Russell; I've caught him in a lie.  I have verified what the former have said against the original texts, but certainly not everything that they say.  I don't have the time.

The world of science relies heavily on faith. Scientists trust one another that they have not lied to the scientific community; for it is not possible for a scientist to repeat every experiment that has been done in the past. They trust the results of the experiment, that is, they trust that the scientist has not falsified data – which happens at times. Recently, there was an article in a local paper about a British doctor who published a study in the late 90s that linked the childhood vaccine for measles-mumps-rubella to autism. The study has now been thoroughly discredited. But note how the article ends: "Most scientists are to be trusted. But our systems are not ideal. We just are implicitly trustful of those we work with."

Relationships of love are, by their very nature, founded upon faith (natural faith).  When another offers me his or her love (whether friendship, marital, or simply good will), I am not certain that the love being offered is genuine.  I do not know with any certainty whether I am loved for my own sake, or loved merely as a means to an end.  But that offer of love awaits a response, and my response is rooted in faith.  If I choose to reciprocate, I open myself up to possible injury (the hurt of rejection); for I have to acknowledge the possibility that the other's love will enhance and enlarge me – hence, I have to acknowledge my perfectibility and reveal it to the other.  In other words, to receive another's love requires humility, an acknowledgment and a disclosure of my finitude.  And so, returning love requires a certain faith that the other will receive me in all my limits.

When a married couple has promised fidelity to one another (from the Latin fides: faith), they have promised to remain faithful, which means he has promised her to remain true to the faith that she has placed in him, and she to remain true to the faith that he has placed in her.

Faith is so pervasive, necessary, and reasonable, because the human person is so limited in knowledge. We have little choice but to rely on one another in a spirit of trust.  Try to imagine what life would be like if you were to refrain from all choices that are based on faith.  You would not trust what your teachers are teaching you until you knew for yourself whether or not what they were teaching is correct.  But how would you know how to read unless you relied on your teachers?  How would you know what to research unless you were taught how to research as well as the names of the figures you wish to research?  You couldn't take your car to the mechanic until you became a mechanic yourself, and you wouldn't trust your doctor until you became a doctor yourself, and a pharmicist yourself, and a chemist yourself, and you wouldn't ever marry another because to give and receive love involves, fundamentally, an act of faith.  Life would come to a stand still.  You couldn't take a taxi, bus, or plane anywhere, because in doing so you are entrusting your life to someone else, all the while believing that they are going to do what they tell you they are going to do, i.e., take you to your destination, drive safely, land the plane, etc.

Supernatural Faith

But what is so ironic is that although we readily trust others who are not entirely trustworthy, we hesitate to trust the One Person who alone is perfectly trustworthy, who cannot lie, who cannot mislead, who has no malice whatsoever in Him, who is all powerful and supremely and perfectly good, and who thus has our best and greatest interests in mind, namely almighty God Himself. If God has chosen to reveal Himself, if He has chosen to come looking for man in order to lead him home, then our way back home to Him will require faith. If God reveals to man truths that surpass human reason, truths that exceed our ability to understand naturally, then the only way to know these truths is through faith, which transcends reason.

But that faith must be of a completely different kind than the natural faith we've been talking about. Natural faith is inadequate, for it cannot assent to supernatural truths. It is reasonable to believe our doctor when he prescribes a medicine – unless there is good reason to suspect that he is untrustworthy – , but how can reason demonstrate that it is reasonable to believe what is completely above reason? It cannot.  To suggest that reason can is to suggest that what exceeds the grasp of reason is within reason's grasp, which is contradictory.  We need to be given the capacity to make that act of faith in what exceeds the grasp of human reason, and what Jesus tells us about himself in the New Testament clearly exceeds reason's ability to demonstrate.  For example, he says: "I am the Way, the Truth, and the Life. No one can come to the Father except through me"; "Anyone who has seen me has seen the Father"; "I am the resurrection. Anyone who believes in me, even though he dies, will live, will never die. Do you believe this?"; "Sky and earth will pass away, but my words will never pass away"; "Before Abraham was, I AM"; "I and the Father are one"; "I am the bread of life"; "It is my Father's will that whoever sees the Son and believes in him should have eternal life, and that I should raise that person up on the last day"; "Anyone who eats my flesh and drinks my blood has eternal life, and I shall raise that person up on the last day"; etc.

On the plane of natural reason, there is no "reason" to believe him. To be able to believe him requires a quality that is above nature (supra nature). This supernatural quality that proportions the soul to these supernatural truths revealed by God, enabling us to believe them if we so choose, is divine grace. According to the Catholic Faith, Baptism imparts that grace, and Baptism infuses the supernatural virtues of faith, hope, and charity into the soul of the baptised, as a sheer gift. And so, if a baptised person eventually stops believing, if he or she has lost his or her faith, it is only because he or she has allowed it die of under nourishment, that is, as a result of not living that faith, of starving it through neglect of prayer and the Eucharist, and typically as a result of welcoming into oneself a spirit of arrogance towards the Faith.  Can an unbaptised person have faith in Jesus?  Indeed, but such faith (whether it is implicit or explicit) is also rooted in grace (prevenient grace).

What enabled the Apostles to immediately drop everything and follow Jesus? They were given this interior capacity to follow him. They still had to choose to cooperate with that interior grace. They could have said no. They chose, however, to cooperate with that grace, not knowing where they were going, and because of that initial decision to trust the Lord, many people share in that supernatural heritage and are heirs to his promises. It all began with Mary's faith, with her fiat: "Let it be done to me according to your word." It continued with the faith of the Apostles, and then the faith of all the great martyrs and saints and missionaries throughout the ages, such as the Canadian martyrs who brought the gospel to Canada back in the 17th century, and it continued with the countless unknown faithful since that time who brought the good news of Christ's resurrection to their families, their students, and their communities.

As was said above, it is impossible not to live on the plane of natural faith, and with just a little thought, the freedom and the tremendous benefits of living on that level are obvious.  Because of that natural faith, we are given the stepping stones that free us to pursue greater goods, such as further knowledge.  We know things about people that we otherwise would not have known, first and foremost, their trustworthiness.  We know others intimately through genuine friendships, and we know the joys of parenting as a result of a marital relationship grounded on fidelity.  In a similar way, supernatural faith opens up a supernatural world that would otherwise be closed off to us.  Of course, reason cannot establish this, as it can explicate the benefits of natural faith; for the starting point of supernatural faith is the grace of supernatural faith itself, not natural reason.  But an analogous experience occurs.  The religiously faithful acquire a new and elevated freedom, and a knowledge of things that would otherwise be closed off to them.

Living on that plane of supernatural faith, we eventually become aware of the supernatural light that permeates our mind and life – if we persist long enough. Our prayers are answered – perhaps not always as we expected – , and we experience an inner strength to face life's difficulties, we experience the ability to forgive those we are unable to forgive before, we sense God's presence in our lives, we feel much less anxiety in life, we don't feel lost as we did before, we begin to see the world from a new angle, we see the hand of God in everyday occurances, and things begin to make sense from the point of view of faith. We don't delight in the things we used to desire, and we see the emptiness of much of what the world honours, and most of all we experience within that we are known and that we are loved by God with a love that is manifest in Christ's passion and death, and we are aware that nothing much matters anymore except making that love known to others. We begin to think of God more, of ways to serve Him and to love Him back. Life becomes joyful, rather than heavy and anxious. All that results from living on the plane of supernatural faith.

The Dangers of Faith

Faith, however, is intrinsically risky.  There is always the possibility that one's trust will be betrayed – except in the case of entrusting oneself to God, who cannot mislead, deceive, or betray anyone.  But how does one minimize this danger or risk factor?   The answer to that question goes back to reason.  If there is a good reason not to trust another, then one ought to be wary of trusting him or her.  If there is no reason not to trust this person and plenty of reasons to trust him, then in light of human limitations, it is reasonable to trust him.  If trusting him requires me to act contrary to reason, it is unreasonable to trust him.  So too with supernatural faith.  Faith transcends reason, which means that it is above reason, not below it.  If what we believe about God is contrary to reason, then there is something defective about the faith, and since God is absolutely perfect, it follows that the article of faith in question cannot be from God.  For example, if one believes that God is calling him to divorce his wife to whom he is validly married in order to marry another, or that He is calling one to donate sperm so that infertile couples may become parents, or that He is calling a person to murder unbelievers, etc., we know that these articles of belief are not from God, since they are contrary to the Natural Moral Law, which is a participation in the Divine Law.  Many of the Mediaeval doctors of the Church (i.e., St. Thomas Aquinas) devoted their lives to becoming masters of human reason in order to demonstrate that what Catholics choose to believe on faith is not contrary to reason. 

C. S. Lewis' "Lord, Liar, Lunatic" argument does not prove that Jesus is who he says he is, but it does demonstrate that it is not irrational to believe his claims, any more than it is irrational to believe your doctor when he tells you that you ought to take this or that medication.  If Jesus is not who he claims to be (the eternal Son of God) and knows that he is not, then he is a liar, and Christianity is the greatest and most influential lie perpetuated in history.  If Jesus is not who he claims to be and does not realize it – thinks he is – , then he is insane.  And since the degree of insanity is measured by the distance that exists between what a person claims to be and what he actually is, Jesus is more insane than the most psychotic individuals that one will find in any psychiatric hospital.  The third option is that he is who he claims to be, the eternal Son of God ("Before Abraham was, I AM").

Of course, this does not prove that Jesus is who he says he is.  Some atheists would agree that he is a liar, and some might even see him as a lunatic.  But even if one does not see him as a liar or a lunatic, one still requires a supernatural quality (divine grace) to make that act of faith in him and his promises, which exceed the grasp of reason.  But the proper safeguard with respect to all matters of faith is that they not fall below the threshhold of human reason.  For God is the author of truth; for God is Truth Itself, and the first law of being of which truth is a property is that contradictories cannot be true at one and the same time.




Deacon Douglas McManaman. "Knowing by Faith." CERC (January 2011).

Printed with permission of Deacon Douglas McManaman.


Doug McManaman is a Deacon and a Religion and Philosophy teacher at Father Michael McGivney Catholic Academy in Markham, Ontario, Canada. He is the past president of the Canadian Fellowship of Catholic Scholars. He maintains the following web site for his students: A Catholic Philosophy and Theology Resource Page, in support of his students. He studied Philosophy at St. Jerome's College in Waterloo, and Theology at the University of Montreal. Deacon McManaman is on the advisory board of the Catholic Education Resource Center.

Copyright © 2011 Douglas McManaman

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