Dr. Looyenga teaches in the Science Department at Calvin College and is a member of Faith Protestant Reformed Church, Jenison, Michigan.

“What then is time? If no one asks me, I know what it is. If I wish to explain it to him who asks, I do not know.” –Saint Augustine

“And God said, Let there be light: and there was light. And God saw the light, that it was good.” Genesis 1:3, 4

The concept “time” is among the most commonly experienced, yet most mysterious, of God’s creatures. I call it a concept because defining time—at least in any meaningful physical sense—is incredibly difficult. Saint Augustine struggled extensively with this question in his Confessions (Book XI) while working to refute some of the heresies regarding creation and reality that plagued the church in his day. The quotation at the beginning of this article reflects the common experience that we all have with time. That is, we all have a sense of time from everyday experience; time is intimately familiar if no one asks too much about the details. But if pressed, we would have a hard time giving time a formal explanation outside our understanding that “things happen” in a specific direction that runs only one way.

This is not to say that having an advanced degree in physics would provide a clear understanding of time. In fact, the problem of defining time has plagued philosophers and scientists alike since the days of the ancient Greeks, and is still essentially unresolved today. From the point of view of modern physics, there is no mathematically precise definition for time, or even any reason why it has to move in one direction.1 As far as the equations that govern our understanding of physical reality are concerned, time can move in either direction and remain mathematically “correct.” But none of us are planning to experience last Tuesday anytime soon; our everyday experience completely defies the idea that this could happen, even if the laws of physics do not.

Which is precisely why our everyday experience isn’t particularly helpful for understanding some of the stranger aspects of time that have been worked out in the past century. As earth-bound creatures with little experience outside of the comfortably predictable confines of our earthly home, our sense is that time is a fixed entity regardless of where we go on earth. Whether on a mountaintop or deep in the sea, our watches would predictably tell us that time is passing at a constant rate, and in a single direction.

Before we go any further into the mysterious science of time, however, it is important that we acknowledge the biblical view of time as a creature of God. Just like the matter and energy that compose the entirety of our universe, time was created by God. This is clear from the fact that Scripture deals with the creation as having a definitive beginning separate from the existence of God, who clearly exists “in eternity”—that is, outside of time (Ps. 90:2; II Tim. 1:9; Rev. 1:8). Furthermore, when the Bible speaks of time, it always does so from an anthropocentric point of view.2 That is, when the Bible speaks of time, it refers to the hours and days that we as humans experience here on earth. The discussion that follows regarding the “relativity” of time is not therefore a license to play “fast-and-loose” with the term in the Bible.

That being said, God has also given us the revelatory power of His creation as another sort of lens through which to see His glory (Belgic Confession, Art. 2). The specific “lenses” we now turn to are the collective laws of modern physics, which provide a mathematical description of what we observe in the creation. From the point of view of physics, time is a “fourth dimension” that acts much like a series of fixed snapshots linked together in order. From this perspective, we can compare the concept of time to the first animated cartoons, which were made by rapidly flipping through a stack of two-dimensional sketches in which the animator’s subjects assumed subtly altered positions that merged into a concerted movement. In the case of time, however, we would need to consider the position of every particle of matter and energy in the three-dimensional space (length x width x height) of the universe, and allow for each and every one to change position in every frame. If strung together into a single, wondrously complex animation, the change in positions of each particle would represent the passing of time—a fourth dimension to space.

But this analogy breaks down on closer examination because all of the components of animated pages in a cartoon sketch move uniformly as you flip through them, whereas time does not. In the case of time, the changes in position of particles throughout the universe would appear different depending on where you were watching the three-dimensional animation unfold. If you were on an incredibly fast-moving space shuttle, they would appear to move more slowly than if you were fixed in place. Similarly, if you were on Jupiter—or some other massive planet or star—time would also seem to pass more slowly than if you were on earth. Strange, but true. Why?

The answer to this strange reality is that God linked together time and space into a marvelously intricate and unified tapestry that physicists have dubbed “spacetime.” Like space, which can be more or less dense in its contents, time is similarly non-uniform across the universe. Because these two entities are actually just different “threads” of the same tapestry, places of high spatial density in the universe that exert strong gravitational forces literally compress time, such that it runs at a different pace relative to places of lower density. Which is an exceedingly strange thing to say, since the word “pace” presumes a rate, that is, something divided by time. Like miles per hour. Or pages per minute. Or words per second. How then can time run at a different rate? How can time have, in effect, different speeds? Is not time itself the “constant” on which we judge rates?

On earth, yes, because every experience we have here happens under essentially the same gravitational force. But in a cosmic sense, no, because gravity is not the same everywhere. Indeed, time is different depending on gravity. This is not just idle conjecture. It was experimentally demonstrated by synchronizing two extremely precise clocks, and then putting one on a commercial jet while the other remained in place on earth.3 Because the effects of gravity are the same as rapid acceleration on a jet, the experiment nicely mimics what high gravity—or high density in space-time—would do to time. Upon return from the flight, the clock on the jet actually showed that time passed more slowly in flight compared to time on the surface of earth. So in the ultimate sense, time is not a fixed entity.

Then what is the constant to which we can calibrate rates, if time is not constant? The answer is the speed of light. This surprising conclusion emerged from Albert Einstein’s work in the mid-twentieth century, and is explained by the laws of General and Special Relativity. Though highly complex in their mathematical basis, the laws of Relativity in their essence reveal (1) that time and space are simply different dimensions of the same thing (“space-time”), and (2) that all rates we measure on earth—or anywhere else—depend on the force of gravity we are experiencing. This ground-breaking work came from Einstein’s unique ability to provide mathematically sound answers to unusual questions, such as what a person would see if he were able to travel at the speed of light.4 Though such questions started as Einstein’s theoretical musings, their answers have provided the basis for our understanding of large astronomical phenomena such as black holes, as well as important physical/chemical relationships between matter and energy, summed up by the well-known equation E=mc2.

But now the most important question of all for us. How does this knowledge—that space and time are interrelated, that both are warped by gravity, and that light is the one constant of physics—bring glory to the Creator? I would point out four God-glorifying aspects that we can extract from the laws of physics regarding space-time and light.

First, it is notable that space and time are not independent, but that they are related to each other as a single, malleable creature—space-time. When we confess that God is the Creator, we also see in His creative acts a clear demonstration of His power and divinity (Rom. 1:19, 20). But I think that we can be even more specific here, and point out that God’s creation of space-time as a single entity also reveals His attributes of being eternal and infinite. Why? Because only a divine being that exists “above” space and “before” time could have created this one marvelous creature. Either/or is not enough; our God must be both eternal and infinite in His being. This is something we pray for as believers when we petition God, “Hallowed be Thy name.” The Heidelberg Catechism (LD 47) reminds us that in this first petition we are asking God to “grant us, first, rightly to know Thee, and to sanctify, glorify, and praise Thee in all Thy works, in which Thy power, wisdom, goodness, justice, mercy, and truth are clearly displayed.” The laws of physics point to the God of Scripture.

Secondly, it is notable that the very first creative act we read of in the Bible is God’s creation of light (Gen. 1). Remarkable! Why? Because as we discussed above, the central constant in our cosmos is this very creature! No matter where you are, no matter how fast you move, no matter when you observe it, light moves at a constant speed. And as such, though we do not read that time was God’s first creation, He in effect made that creature too when He fashioned light as His first creature. And so while Einstein’s work may have pointed to the primacy of light as a constant, it was our heavenly Father who fashioned it to be His standard for the physical laws governing the Creation. A mere coincidence, says the scoffer. No, say we, a providential work of the Creator!

In the third place, I would point out that God’s omnipotence over time is not only key to our understanding His creative power, but also to understanding the possibility of the cross. It was there that our Lord Jesus Christ suffered for sin, conquering it completely and atoning for sin such that we may have fellowship with God. But the puzzling thing about that atonement is that our Lord accomplished it in the space of just three hours. Stop and think about that. Complete atonement for an eternity of punishment for sin—in just three hours. No mere man could do this, regardless of his perfection, because no man could bear eternity in the space of time, regardless of its length. But we confess that Christ was not only man; He is God incarnate! As fully divine, He was able to bear an eternity’s worth of suffering for all His people, compressed into a temporal space of three hours. No man could do this; but “with God nothing shall be impossible.” (Luke 1:37).

The last thing I would draw to the reader’s attention is how points two and three connect. Recall that during the three hours of suffering on the cross, the earth was bathed in darkness, as recorded by three gospel accounts (Matt. 27:45; Mark 15:33; Luke 23:44–45). This event no doubt has many facets of significance. For instance, we see that the “light of the world” Himself (John 8:12) was obscured in hellish agonies; that the darkness of our sins was exposed on the cross (I John 1:5-7); and that the clear judgment of God for sin was being executed (Ex. 10:21-23).

But again, I think we can say more. If light—the first of God’s creatures—is the standard for time, its absence at the cross implies the weight of eternity being experienced by Christ. No, I am not saying that time stopped at the cross. But for Christ, experiencing the hellish agonies of eternity, time ceased to exist. And to tell us that eternity was being accomplished, and that time no longer had meaning, God removed the standard—for a little while. But when the weight of eternity was accomplished, the light returned. No longer a standard looking forward to victory, but a standard for counting the days until the Light would return as victorious Lord of the creation!

1 Tracy, Gene. “A science without time.” April 25, 2016, https://aeon.co/essays/why-doesn-t-physics-help-us-to-understand-the-flow-of-time.

2 Mortenson, Terry. “Real Time or ‘God’s Time’?” Jan. 1, 2012, https://answersingenesis.org/genesis/real-time-or-gods-time.

3 This is the famous “Hafele-Keating experiment” performed in 1971 using ultra-precise atomic clocks. Science, Jul. 14, 1972;177 (4044):166-8, http://science.sciencemag.org/content/177/4044/166.long.

4 Einstein’s thoughts on hearing a bell tower sound the hour are a great example of how simple questions can lead to remarkable scientific insights. To read more on this see: http://www.bbc.com/travel/story/20160901-the-clock-that-changed-the-meaning-of-time.