Appeared in Winter 1995 | Vol. XXI, No. 4

Twentieth Anniversary Issue

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In the Christian tradition, “light” is a term that has extensive significance. A goodly variety of philosophers, theologians, and poets have made remarkably insightful contributions to Christianity’s highly developed and beautifully integrated understanding of “light.” This essay will explore the Christian meaning of light, and its significance for a world of skepticism, relativism, and cynicism.

Among the many outstanding thinkers who have made important contributions to the continuing discussion of light, few have equalled St. Bonaventure for depth of insight, breadth of conception, and richness of expression. The Seraphic Doctor brings to bear, in his treatment of light, a mind that is at once theological, philosophical, and poetic. We find a good example of this threefold habitus in his Breviloquiumwhere he explains the six days of creation in relation to varying degrees of light ranging from the luminous to the translucent and finally to the opaque.1

The luminous is represented on the first day of creation when God separated light from darkness. The translucent is evident on the following day when He divided the waters from the firmament. The opaque is manifested on the next day when God separated the land from the waters. Collectively, these three days show us how division reveals Divine wisdom. God manifests His wisdom through a series of divisions that allows the emergence of light, water, and land. It should be clear that such a series of events illustrates a direction that God’s creation is taking, one that is moving from the more general and numinous to the more specific and concrete.

The next three days of creation display a recurrence of the progression from luminosity to translucence to opacity. But in this second triad, God is manifesting not the wisdom that is associated with division, but the goodness that is associated with provision.Thus, on the fourth day, God adorns the heavens with lights: the stars, sun, and moon. The following day He brings fish and birds from the water. On the sixth day, He brings forth land animals: mammals, reptiles, other beasts, and finally man. In these latter three days, as God moves from luminosity to translucence to opacity, He is revealing His providence (or goodness) by providingus with beauty,food, and companionship.2

At the same time, another triad is involved. Whereas the first three days reveal God’s wisdom, and the next three days His goodness,the essential and abiding fact of creation manifests God’s power. God, therefore, who begins creation with light and proceeds to translucence and opacity, intends creation to take place over a period of six days so that He can clearly and distinctly manifest to us three essential features of His personality, namely, that He is omnipotent, all-wise, and all-beneficent.3

St. Bonaventure reminds us, in his intricately balanced explanation of the Genesis account of creation, that God is speaking to us in a most personal way, that He wants us to know about His power, wisdom, and goodness. He wants us to know about these divine attributes because He wants us to feel comfortable in the knowledge that God is not only the creator, but a wise one who is generous and provident. He wants us to feel assured and confident – at home, so to speak – as inhabitants of the world He created. He created the world for us and will not abandon us in our times of need.

In addition, when God declared that “light” is good, He was calling attention to the existence of yet another trilogy. As the cause of being, light is powerful; as the cause of understanding, light is clear; as the cause of ordering life, light is good.4 Bonaventure’s position on this particular threefold significance of light is solidly in harmony with traditional Christian teaching on the meaning of light. It is firmly rooted in Scripture and its practical implications have been continuously reaffirmed by human experience. At the same time, however, it stands in opposition to the relativism, skepticism, and cynicism that characterizes much of contemporary thought.

As the cause of being, light is distinguishable from darkness which has no capacity for causation whatsoever. Light causes being; darkness, since it is nothing, cannot cause anything. Hence light and darkness have nothing in common. Light is;darkness is not. Light is a source of illumination; darkness is not. Light dispels darkness; darknesscannot dispel light. Contemporary relativism, however, tends to place light and darkness on an equal metaphysical footing. For example, strict relativists, who do not anchor their choices in the firm foundation of real being, regard choice to be self-justifying. That is, they affirm choice apart from any consideration as to whether it relates to the real world. The choice to abort, for relativists, proceeds independently of any knowledge of the nature of what one is doing or likely consequences that will follow. Thus, “pro choice” advocates staunchly oppose any kind of illumination that would shed light on the nature of the fetus, the psychological or physical consequences of abortion, as well as the logical impact abortion has on marriage, the family, and society. As far as the “pro-choice” position is concerned, light and darkness are equally irrelevant.



In The Closing of the American Mind, author Allan Bloom bemoans the widespread relativism he observes among university students, a relativism that is uprooted from real norms and consequently divorced from the kind of helpful illumination that philosophical thinking can provide. Relativists characteristically eschew illumination for fear that it will impose unwanted obligations on them or interfere with their freedom and individuality. They appear indifferent not only to the fact that light brought them into being while darkness did not, but that light is the indispensable source of meaning for who they are and everything they do. There is no true morality apart from light and the illumination that it provides. Relativists act as if what light brought into being simply does not exist.

As the cause of understanding, light was considered an indisputable ally until 1927 when physicist Werner Heisenberg described his famous “Principle of Indeterminacy.” According to Heisenberg, it is not possible to determine the position and velocity of an electron. The reason for this is that photons of ordinary light exert a violent force on electrons thereby altering both their position and velocity. The scientist who views the electrons with an extremely high-powered electron microscope is not seeing things as they are in themselves (or as they would have been had he not tried to see them). His very act of seeing intrudes upon them. Light actually interferes with knowing the electrons in their objectivity. The observer is at the same time both a spectator and an actor in the drama. The “Principle of Indeterminacy” states that light prevents knowledge. And when the physicist computes the mathematical margin of uncertainty in his measurements of an electron’s position and velocity, he finds it is always a function of that mysterious quantity known as “Planck’s Constant.”

Thus light, in being a cause of uncertainty, becomes a source of skepticism. We cannot know without light, and if light itself is a source of confusion, then skepticism must replace truth. The best of our intellectual operations, therefore, are restricted to the shadowland of probability.

As the cause of ordering life, light is now regarded with a great deal of suspicion. Intense or excessive light is known to cause a wide range of discomforts and diseases from sunburn to skin cancer. Light can be irritating, blinding, glaring, dazzling, and distracting. As T.S. Eliot has said of modern man:

In our rhythm of earthly life we tire of light. We are glad when the day ends, when the play ends; and ecstasy is too much pain.5

Light can be tiring and painful. The time comes when we need darkness and sleep. In Johann Peter Hebel’s Nibelungen,we find a much stronger opposition to light. When Brunhilda reaches the bright lands of Burgundy, having left her own country where an eternal night reigns, she exclaims:

I cannot get accustomed to so much light,

It hurts me, I feel as though I am going about naked,

As though no gown here would be thick enough!6

Because light can be so powerful a disvalue with regard to the ordering of life, inasmuch as it is something we need to be relieved or protected from, it can be an occasion for cynicism.

Light and analogy:

The critical question here concerning light has to do with the relationship between specific forms of light such as mental illumination, photons, and sunlight, and more numinous notions of light such as those referring to God and creation. In other words, are the latter references to light simply metaphors of the former, having nothing in common with them with respect totheir intrinsic and formal natures? This question has an important bearing on the Christian or theological meaning of light. Is such meaning a mere poetic fancy or is it real and therefore discloses to us a truth we can, at least to a certain extent, grasp? Is the word “light” as applied to God and creation merely a word and nothing more or does it bespeak a reality that touches us and informs us with meaning?

Aquinas deals with this question in a wide assortment of texts and comes to a conclusion that is in fundamental agreement with Bonaventure and the intellectual mentor of this 13th century Franciscan, St. Augustine.

St. Thomas distinguishes between an analogy of similarity (similitudoanalogiae) and an analogy of proportionality (similitudo proportionalitatis).7In the former case, things have a likeness to each other by sharing the same quality, such as different things that are hot. In the latter case, things are like each other by a certain proportionateness. For example, the Scriptures speak of God as the sun because He is the principle of the spiritual life just as the sun is the principle of corporeal life. In this instance the word “sun” is applied to God metaphorically and does not disclose anything about God’s nature. God and the sun do not share the same nature or reality. Similarly, when Christ is referred to as a “lion,” the term is also used metaphorically and does not signify anything about Christ himself. The word “lion,” though predicated of Christ, does not refer to Christ’s nature. It refers to Him not really, but metaphorically. If all lions were assembled, Christ would not be present.

In another text, Aquinas asks the question whether light is said to be properly [that is, non-metaphorically] of spiritual things.8On the one hand, St. Thomas argues that since nothing per se sensible can be common to itself and a spiritual thing which is not per se sensible, light is predicated of spiritual things metaphorically. The proper meaning of “light” (its ratio propria) belongs to matter and refers to what the eye sees. Yet Aquinas goes beyond this point and explains how it can be said that corporeal and spiritual things do share light as a common reality.

According to Aquinas, there is a common notion (ratio communis) that the “light” of spiritual and corporeal things share, namely, a “principle of manifestation.” St. Thomas states that “intellectual light is nothing else than a manifestation of truth” and supports this claim by quoting Ephesians v. 13 which reads: “All that is made manifest is light.”9The notion of a “principle of manifestation” bears no reference to matter and shares a common reality among all things that manifest light. If we consider the things which fall under this common signification (secundum ordinem rerum), we can understand how light applies to spiritual things more properly than it does to things that are material. As St. Thomas states, “Light is more truly in spiritual things than in corporeal things, not according to the proper meaning of light, but according to the principle ofmanifestation. “10

In this sense, by referring to light as a principle of manifestation, as something that all things that manifest light share, we have a true and proper analogy and are not merely using the word light as a metaphor.11Thus, the word light as applied to God and creation does disclose something of their realities. Moreover, light is more perfectly manifested in those beings that are more perfectly adapted to manifest it. Therefore, “light” is more perfectly manifested in God than in the human mind, in photons, or in sunlight. And it is more perfectly manifested in the human mind than it is in photons and in sunlight.

By understanding how the word “light” is used as a proper analogy, we have reason to state that any kind of light which is an occasion for relativism, skepticism, or cynicism, is operating in a way that is essentially “un-lightlike” since it contradicts its proper activity as being a principle of manifestation. Light must manifest. That is its essence. Therefore, it cannot be a cause or occasion for relativism, skepticism, or cynicism. The modern world is less comprehending of light than it is fearful of it.

Dante on light:

It has been said that Dante’s Divine Comedy is in reality the theology and philosophy of St. Thomas Aquinas set to poetry. There can be little doubt that Dante’s treatment of light closely follows that of the Angelic Doctor. The opening lines of the “Paradiso” express how the light from God shines throughout the universe and is absorbed and reflected in different ways: “La gloria di colui che tutto move per 1’universo penetra, e risplende in una parte piu e meno in altrove” (The glory (la luce di Dio] of the One who moves all things penetrates the universe and reverberates [re-glows] more in one part and less in another). For Dante, God’s light penetrates to the essence of things and their response is not a mere surface reflection but a refulgence or re-glowing that emanates from the very core of their being. From the opening of the “Paradiso,” Dante begins to orchestrate a veritable symphony of light.

As a way of elaborating on this notion, Dante states later in the poem (Canto XXXI) the following: “La luce divina e penetrante per 1’universo secondo ch’e degno” (The light of God penetrates the universe according to the dignity of each part). Just as Aquinas teaches that being belongs intrinsically to all that is and to each and every thing in proportion to its specific nature, Dante is expressing a similar notion, namely that each being receives and manifests light in accordance with the specific nature of its own being. Like Aquinas, Dante holds that greater intensity of light signifies greater spirituality. They both agree that God is the supreme and perfect light who is a principle of manifestation without possessing any trace of imperfection or limitation. The imperfect or limited way of receiving and reflecting light belongs to His creatures.

Light as God:

Through analogy we begin to see how the universe holds together, how the many can participate in the One. It also gives us insight into the hierarchical organization of being and teaches us something about the relationship between God and creation. In addition, it helps us to understand how a quality such as “light” can exist most perfectly and pre-eminently in a being,God, that is most removed from our senses. As it states in Timothy 6:16: “God inhabiteth light inaccessible, where no man hath seen nor can see.”

When St. John states that “God is light” (I John 1:15), he is implying that God is pre-eminently light, that is, light in an original, perfect, and complete way. Therefore, light must be attributed to all other things in a secondary, less perfect, less complete way. God is the fullness of light. All other light is inferior to the Divine Light. Whatever imperfections created light may have are not to be found in God. The Divine Light can not interfere with knowledge, confuse, impose, fade, overwhelm or cause pain. This is why Plato could say that “Light is the shadow of God” and John Lord, a 19th century American historian, could write that “The light of nature, the light of science, and the light of reason, are but as darkness, compared with the divine light which shines only from the word of God.”

We hope to be able to discern, as C. S. Lewis has expressd it, “`patches of Godlight’ in the woods of our experience.”12Or, to employ aquatic imagery rather than sylvan, T. S. Eliot has stated:

Our gaze is submarine, our eyes look upward

And see the light that fractures through unquiet water.

We see the light but see not whence it comes. O Light Invisible, we glorify Thee!13


God’s light penetrates through woods and waters, through darkness and obscurity. As it searches out the deepest hiding places, it remains ever inextinguishable. Light, therefore, is also Hope and Love as well as Truth.

It is not the study of corporeal light that enlightens us about the Divine Light. Rather, it is the absolute Light of God that illumines every other light. It is God who is the source of every illumination in the universe, “the true light that enlightens every man who comes into the world” (John 1:19). God’s light is to our intellect as the light of our intellect is to the body. Hence it is said: “The lamp of the body is thy eye. If thy eye be sound, thy whole body will be full of light. But if it be evil, thy body also will be full of darkness. Take care, therefore, that the light that is in thee is not darkness. If, then, thy whole body is full of light, having no part in darkness, it will all be illumined, as when a bright lamp illumines thee” (Luke 11:34-36). “In thy light do we see light,” the psalmist writes (36:9). There would be no earthly light if it were not for the Divine Light. We see light and the things that light illuminates. Light gives us knowledge, but it points to something above knowledge – a sense of the transcendent God, the Light above light. To see the light without sensing the Light is to be spiritually blind. God bathes us in his eternal light so that we may see all things.

T. S. Eliot praises God who is “Light Invisible … Too bright for mortal vision.”14We put the whole cosmos in perspective during Mass when we set little lights on the altar to honor the Invisible Light. Even the darkness can remind us of the light, and the light can draw us to the Light Invisible. We praise the Greater light for giving us the lesser lights. The light breaking through the stained glass window fills us with awe because it triumphs over darkness, and wonder because it reminds us of its divine source.

When John Henry Cardinal Newman was journeying home from Italy, in 1832, he became deliriously ill. With death hovering near, he gave final instructions to his Italian servant, but then suddenly added these unexpected words: “I shall not die, I shall not die, for I have not sinned against the light …God has still a work for me to do.”

With difficulty, he reached Palermo. He crossed the Mediterranean, then France, and was sailing home when his vessel was becalmed in the Straits of Bonifaccio. While walking the deck and gazing up at the darkened sky, he composed Lead, Kindly Light. The first stanza of the poem is an eloquent and haunting image of this faithful apostle of the light:

Lead, kindly light, amid the encircling gloom,

Lead Thou me on!

The night is dark, and I am far from home.

Lead Thou me on!

The adjective “kindly” is of particular significance here. The Divine Light is not only a source of illumination, but it is also a source of love. Lucifer, whose name means “bearer of light,” has knowledge, but lacks love. Newman is reminding us that the God of Light is also the God of Love. To separate love from light is to create Hell.

Newman could anticipate daybreak despite the enveloping darkness. (It may be interesting to note here that the Greek words for darkness and daybreak [luge and luke] are etymologically related.) For the Christian, darkness is always a prelude to daybreak because he has faith in the Light even when his eye sees only darkness.

Light and the Trinity:

At the basis of the Arian heresy is the inability to understand how the Father and the Son, the first two persons of the Blessed Trinity, can share the same essence. If God the Father is Light in a pre-eminent way, how can His Son who proceeds from Him be Light in an undiminished way?

Athanasius, who successfully and brilliantly repudiated the Arian heresy, reasons that since Christ cannot be a creature or someone created out of nothing, He must be the very offspring of the Father. In describing the relationship between the Father and the Son, Athanasius alluded to the relationship that exists between light and radiance:

Who will presume to say that the Radiance is unlike and foreign from the sun? Rather who, thus considering the radiance relatively to the sun, and the identity of the light, would say with confidence, “Truly the light and the radiance are one, and the one is manifested in the other, and the radiance is in the sun, so that whoso sees this, sees that also”?

Arius had insisted that the Son had a beginning in time, that there was a time when the Son was not. Elaborating further on the paradox of a Trinity in which there is indivisible unity, Athanasius states:

The radiance also is light, not second to the sun, not a different light, nor from participation of it, but a whole and proper offspring to it. And such an offspring is necessarily one light; and no one would say that they are two lights, but sun and radiance two, yet one the light from the sun enlightening in its radiance all things. So also the Godhead of the Son is the Father’s; whence it is indivisible; and thus there is one God and none other but he.

In one sense we can distinguish the light of the sun from its radiance. The sun itself, which remains 92 million miles away from us, is not the same as the sunlight that reaches us. At the same time, they are one. If the sun is extinguished, its sunlight is extinguished along with it. The Son and the Father are inseparable (though distinguishable) and belong to the same essence (homoousios) in the same way that radiance and light are. “If anyone,” wrote Denis the Pseudo-Areopagite, “dares to separate the radiance from the light and to say that the radiance is of another essence, let him join Arius in his insanity; for such a person has lost even the resemblance of human intelligence.”

Athanasius reiterated the point in hisOrations against the Arians:

 What the light enlightens, that the radiance irradiates; and what the radiance irradiates, from the light is its enlightenment. Thus also when the Son is beheld, so is the Father, for he is the Father’s radiance; and hence the Father and the Son are one.

Christ is, indeed, “Light from Light.”

St. John had paved the way for Athanasius and the Nicaean Creed by stating repeatedly that Christ brings the true light to the world: “I am the light of the world. He who follows me does not walk in darkness, but will have the light of life” (8:12); “As long as I am in the world I am the light of the world” (9:05); “Whileyou have the light, believe in the light, that you may become sons of light” (12:36); “I have come a light into the world, that whoever believes in me may not remain in the darkness” (12:46).

In conclusion, light, for the Christian, has a rich, positive, analogical meaning that embraces a wide range of realities culminating in the affirmation of the Trinitarian God and His beneficent relationship with all of creation. As such, it stands as a bulwark against contemporary trends toward relativism, skepticism, and cynicism.

The very word “light” contains an interesting, though purely accidental, summation of its Christian significance. We may consider the letters “1,” “i,” “h,” and “t” as standing for love, illumination, hierarchy, and truth; while regarding the silent, unpronounced letter “g” at the core as representing God, the hidden source from whom all the goods of creation proceed.





1St. Bonaventure, “The Breviloquium-II,” The Works of Bonaventure, Vol. II, tr. by Jose de Vinck (Paterson, N.J.: St. Anthony Guild Press, 1970), pp. 72-75. Subsequent references to this series of volumes will be designated as Works.

2Ibid. p. 74.

3Ibid. p. 72.

4Works, Vol. V, “Fifth Collation,” p. 73.

5T.S. Eliot, “Choruses from `The Rock’,” The Complete Poems and Plays, 1909-1950 (New York: Harcourt Brace & World, 1952), p. 112.        

6Hebe1,The Nibelungs, “The Death of Siegfried,” Act. II, scene vi.

7Suppl. q.69, al, ad 2.

8IISent., d. 13, q.1, a.2.

91, q.106, a.l.

10II Sent., d.13, q.1, a.2: “Lux verizcs est in spiritualibus quam in corporalibus, non secundum propriam rationem laccis, sed secundum rationem manifestiationis.”  

111, q.67, a.1: “But if taken in its common and extended use, as applied to manifestation of every kind, it [light] may properly be applied to spiritual things.”

12C. S. Lewis, Prayer: Letters to Malcolm (Glasgow: Collins, 1964), p. 93.

13Eliot,op. cit., p. 113.

14Ibid., p.114.