When is a day not a day? That question lies at the heart of a pivotal and long-standing argument against the literal interpretation of the creation account in Genesis 1, commonly known as the Day-Age theory.
Day-Age proponents attempt to read incalculable stretches of time into the white spaces of Genesis 1, starting with the biblical account of God’s activity on that first day of creation:
In the beginning God created the heavens and the earth. The earth was formless and void, and darkness was over the surface of the deep, and the Spirit of God was moving over the surface of the waters. Then God said, “Let there be light”; and there was light. God saw that the light was good; and God separated the light from the darkness. God called the light day, and the darkness He called night. And there was evening and there was morning, one day. (Genesis 1:1–5)
The first day of creation defines what the Bible means by the word day throughout the context of the first chapter of Genesis. Those who believe the days of creation were long ages invariably make much of the fact that the sun was not created until the fourth day, and on this basis they argue that the days could not have been solar, twenty–four–hour days. The word day, they point out, is used elsewhere in Scripture to speak of long or indeterminate periods of time.
For example, “the day of the Lord” is an expression used throughout Scripture to signify an eschatological era in which God pours out His wrath upon the earth. Moreover, 2 Peter 3:8 says, “With the Lord one day is like a thousand years, and a thousand years like one day.” Thus old–earth creationists argue that the days of creation might well have been long eras that roughly correspond to modern geological theories about the so–called Precambrian, Paleozoic, Mesozoic, Tertiary, and Quaternary eras.
The problem with this view is that nothing in the passage itself suggests that the days were long epochs. The days are defined in Genesis 1:5: “God called the light day, and the darkness He called night. And there was evening and there was morning, one day.” Night and day, evening and morning are demarcated by rhythmic phases of light and darkness from the very beginning. The very same expression, “there was evening and there was morning, a [nth] day” is employed for each of the six days of creation (vv. 8, 13, 19, 23, 31), underscoring the fact that the days were the same and that they had clearly defined boundaries.
The only cadence of light and darkness defined anywhere in this context is the day–night cycle that (after day four) is governed by the sun and moon (Genesis 1:18). There is no reason to believe the rhythm was greatly altered on day four. That means the duration of “the evening and the morning” on the first day of creation was the same as the evening and morning of any solar day.
Indeed, the word day is sometimes used figuratively in Scripture to speak of an indeterminate period of time (“the day of your gladness”—Numbers 10:10). But throughout Scripture, wherever the word is modified by a number (“He was raised on the third day”—1 Corinthians 15:4), the clear reference is to a normal solar day.
Nothing in Scripture itself permits the view that the days of creation were anything other than literal twenty–four–hour days. Only extrabiblical influences—such as the theories of modern science, the views of higher criticism, or other attacks against the historicity of Scripture—would lead anyone to interpret the days of Genesis 1 as long epochs. In effect, old–earth creationists have subjugated Scripture to certain theories currently popular in big bang cosmology. Cosmological theories have been imposed on Scripture as an interpretive grid and allowed to redefine the length of the creation days.
Such an approach is not evangelical, and because it compromises the authority of Scripture at the start, it will inevitably move people away from an evangelical understanding of Scripture, no matter how tenaciously the proponents of the view attempt to hold to evangelical doctrine. To accommodate our understanding of Scripture to secular and scientific theory is to undermine biblical authority.
An Augustinian Problem?
Hugh Ross and other old–earth creationists respond to this argument by pointing out that Augustine and certain other church fathers interpreted the days of creation nonliterally. “Their scriptural views cannot be said to have been shaped to accommodate secular opinion,” Ross claims.  Hugh Ross, The Fingerprint of God (New Kensington, PA: Whitaker House, 1989), 141.
Indeed, Augustine did take a nonliteral view of the six days of creation. He wrote, “What kind of days these were it is extremely difficult, or perhaps impossible for us to conceive, and how much more to say!”  Augustine, The City of God, 11:6.
But what Ross doesn’t tell his readers is that Augustine and those who shared his views were arguing that God created the entire universe instantly, in a less than a nanosecond—indeed, outside the realm of time completely. Far from agreeing with Ross and modern science that creation was spread over billions of years, Augustine and others who shared his view went the opposite direction and foreshortened the time of creation to a single instant.
They did this because they had been influenced by Greek philosophy to believe that a God who transcends time and space could not create in the realm of time. So they collapsed the six days to a single instant. Augustine wrote, “Assuredly the world was made, not in time, but simultaneously with time.”  The City of God, 11:6. That was precisely what Augustine’s study of the works of secular philosophers had taught him. In other words, his views on this question were, after all, an accommodation to secular opinion. (And such opinions did eventually erode the early church’s commitment to the authority of Scripture.)
However, Augustine opposed the notion of an ancient earth as vigorously as any modern evangelical critic of old–earthism. He included an entire chapter in The City of God titled, “Of the Falseness of the History Which Allots Many Thousand Years to the World’s Past.” His criticism of those who believed the earth is ancient was straightforward:
They say what they think, not what they know. They are deceived, too, by those highly mendacious documents which profess to give the history of many thousand years, though, reckoning by the sacred writings, we find that not 6,000 years have yet passed.  The City of God, 12:10.
Sowing Confusion into Scripture’s Clarity
Indeed, nothing in Scripture itself would ever lead anyone to think that the world is billions of years old or that the days of creation were long eras. Instead, by defining the days of creation according to the light cycle that separates day from night, Scripture states as explicitly as possible that the days of creation were equal in length to normal solar days. And part of the wonder of creation is the ease and speed with which God formed something so unimaginably vast, complex, intricate, and beautiful. The emphasis is not, as Hugh Ross suggests, on “time and attention to detail.”  The Fingerprint of God, 160.Rather, what the biblical account aims to stress is the infinite majesty and power of the Almighty One who accomplished so much, so perfectly, in so short a time, with nothing more than His word.
Old–earth creationism diminishes the biblical emphasis on creation by divine fiat, setting up a scenario where God tinkers with creation over long epochs until the world is finally ready to be inhabited by humans made in His image. This is quite contrary to what Genesis teaches.
That is not to suggest, as Augustine did, that everything was created in an instant. According to Scripture, there is a progression to God’s creative work. He did it over six days’ time and rested on the seventh day. This is not because He needed that much time to create, and certainly not because He needed the rest. But He thereby gave a pattern for the cycle of work and rest He deemed right for humanity to live by. This established the measure of a week, which to this day is reflected in the calendar by which the entire world measures time.
The specificity of Genesis 1:1-5 is undeniable. God’s people must not surrender the details of the creation narrative to be redefined or reinterpreted by those whose agenda is to dethrone God. We must hold to the clear testimony of Scripture and the authority of God’s Word against all assaults. And we must not be intimidated into modifying our view or the Bible to accommodate and appease an aggressively secular society or its “scientific” standard.
(Adapted from The Battle for the Beginning.)