When the Holy See announced in late July that John Henry Newman was soon to be declared the 38th doctor of the church, speculation immediately arose about how Newman would be known. Doctors of the church are often given some sort of informal nickname that emphasizes their particular contributions to the tradition. St. Irenaeus, the last figure before Newman added to their number in 2022, is the Doctor of Unity. St. Teresa of Ávila, added to the roster in 1970, is the Doctor of Prayer. St. Bernard of Clairvaux, from the Cistercian reform of the Benedictine tradition, is the Doctor mellifluus, the Mellifluous Doctor, as his teaching was “as sweet as honey.” 

How, then, will St. John Henry Newman, who will be declared a doctor of the church on Nov. 1, the Solemnity of All Saints, be known? He could be the doctor of the development of Christian doctrine, of faith and reason, of conversions, of Christian friendship. All of these epithets—and more—are appropriate for the new doctor. Yet there is one title that seems to be repeated with some frequency, as it is a theme often attached to Newman and is certainly present in his considerable theological corpus: Doctor of Conscience.

Newman would be comfortable with Aquinas’s notion of conscience—an act of reason by which universal moral knowledge is applied to a particular situation—but his work also has unique emphases that deserve attention. What are some of the specific features of Newman’s approach to conscience?

The Voice of Christ

Newman’s most famous statement on conscience (and perhaps the most famous single quote in his entire corpus) can be found in his “Letter to the Duke of Norfolk,” where he gives one of the more famous toasts in world literature: “I shall drink—to the Pope if you please—still, to Conscience first, and to the Pope afterwards.” When this passage is cited, it is often assumed that Newman is somehow setting up an opposition between the teaching authority of the church and personal conscience. Nothing could be further from the truth.

While the letter does describe scenarios in which a conscientious Catholic could disagree with practical (i.e., non-doctrinal) decisions a pope might make, in no way is Newman establishing a necessary conflict between personal conscience and the teaching authority of the church. For Newman, that teaching authority rests on the power of conscience. Far from being a limiting force on conscience for Newman, the Catholic Church should be conscience’s greatest champion. 

In a speech to the U.S. bishops in Dallas in 1991, Cardinal Joseph Ratzinger effectively summarized Newman’s view: 

And in contrast to mistaken forms of ultra-Montanism, Newman embraced an interpretation of the papacy, which is only then correctly conceived when it is viewed together with the primacy of conscience—a papacy not put in opposition to the primacy of conscience but based on it and guaranteeing it. Modern man, who presupposes the opposition of authority to subjectivity, has difficulty understanding this.

Newman effectively provides the response to Stalin’s famous question: “How many divisions does the pope have?” The power of the papacy is not in the force of arms but the force of human conscience. It is fitting, therefore, that the modern papacy has become a great champion of the rights of conscience, a key aspect of human dignity.

In his writings, Newman tends to describe conscience more consistently than he precisely defines it. In the Grammar of Assent, he refers to conscience as “the aboriginal Vicar of Christ.” For Newman, one’s conscience is not a form of radical subjectivity, but rather the voice of another in the mind and heart. His is a fairly elevated approach to conscience: 

The supremacy of conscience is the essence of natural religion; the supremacy of Apostle, or Pope, or Church, or Bishop, is the essence of revealed; and when such external authority is taken away, the mind falls back again of necessity on that inward guide which it possessed even before Revelation was vouchsafed.

In an analogous way to the role of the papacy in determining questions of faith and morals, one’s conscience provides the immediate and direct voice of Christ within the soul. The closest Newman comes to a systematic definition of conscience is in the “Letter to the Duke of Norfolk,” where Newman speaks of conscience as “the voice of God in the nature and heart of man, as distinct from the voice of Revelation…the internal witness of both the existence and law of God.” This is why for Newman, there is such an imperative on absolute obedience to one’s conscience (presuming, of course, that one has taken the trouble to form it well—more on that below). For Newman, obedience to conscience is obedience to the voice of God resounding in the mind and heart.

Newman’s views on conscience lead to what many commentators feel is an implicit proof for the existence of God from conscience. He suggests that because we feel pride or guilt when reflecting on our moral choices, there must be someone before whom we feel that pride or guilt. That someone is God. As he phrases it in his Apologia Pro Vita Sua, “Thus conscience, the existence of which we cannot deny, is a proof of the doctrine of a Moral Governor…the doctrine of a Judge and Judgment to come is a development of the phenomenon of conscience.” Because the human person has a conscience, Newman thinks it reasonable to conclude that a supreme being exists.

Conscience and Truth

Following thinkers like Aquinas, Newman would be quite comfortable with the two traditional functions of conscience. One of those functions is called synderesis, innate moral knowledge of general principles: Do good, avoid evil. The other function is syneidesis, the Greek word for conscience, which is the application of those general principles to particular cases. If one has a well-formed conscience, one would know that it is good to help the poor (synderesis); the function of syneidesis would be the judgment of reason about what I should concretely do when I encounter this particular poor person asking for assistance. 

Newman is not alone in noting that it can be easier to know general moral principles than precisely how to apply them in given circumstances: “The natural voice of Conscience is far more imperative in testifying and enforcing a rule of duty, than successful in determining that duty in particular cases.”

Newman would not be comfortable with the notion that the sincere effort to follow one’s conscience necessarily means that one’s choices are right; he is quite clear that conscience can err. He writes, “It may be objected, indeed, that conscience is not infallible; it is true, but it is still ever to be obeyed.” What is remarkable about his view is that the sincere effort to form and follow one’s conscience will ultimately lead one to deeper virtue and greater truth:

[Conscience] mistakes error for truth; and yet we believe that on the whole, and even in those cases where it is ill-instructed, if its voice be diligently obeyed, it will gradually be cleared, simplified, and perfected, so that minds, starting differently will, if honest, in course of time converge to one and the same truth.

For Newman, even following a conscience that is both sincere and erring will lead one ever closer to truth. If I make a sincere effort to form my conscience well, and am diligent about obeying the dictates of my conscience, Newman holds, I will draw ever closer to both goodness and holiness.

The imperative to form the conscience well remains, of course, and in Grammar of Assent Newman introduces a favorite image for conscience: a clock. Like all timepieces, consciences need to be regulated (or formed): “Our conscience too may be said to strike the hours, and will strike them wrongly, unless it be duly regulated for the performance of its proper function.” Yet simply because conscience can err does not disprove its authority, or demonstrate an inability to arrive at moral certainty in matters that cannot be empirically proven. We follow the clock, and we attempt to make sure that the clock accurately reflects the time.

Out of the Shadows

The designation of John Henry Newman as a doctor of the church is a cause for joy for the whole church. This process has spanned multiple pontificates: While his cause for canonization was opened in 1958, it was Pope John Paul II who proclaimed him venerable in 1991, Pope Benedict XVI who beatified him in 2010 and Pope Francis who canonized him in 2019. 

Pope Francis was eager to declare Newman a doctor of the church during the Jubilee of Hope, but that task has fallen to Pope Leo XIV, who is taking this step at an early moment in his pontificate. On Oct. 22, the Vatican announced that St. John Henry would be the co-patron of Catholic education, along with St. Thomas Aquinas.

Newman’s theological contributions are manifold. He is seen by many as pointing the way toward the Second Vatican Council, and some have argued there is no greater theological mind in the English language. His views on conscience are a critical part of his contribution. Conscience is a key theme not only for Newman but for the whole contemporary church—not as a concept to be used to justify radical subjectivity, but as the way to moral integrity.

If I form my conscience well and follow it diligently, I am inevitably moved, as was inscribed on Newman’s gravestone, ex umbris et imaginibus in veritatem: “from shadows and images into Truth.”

This article appears in December 2025.

Nickolas Becker, O.S.B., is a Benedictine monk of Saint John’s Abbey in Collegeville, Minn., and a visiting assistant professor of theology at the College of Saint Benedict and Saint John’s University.