One of the common objections to biblical creation is that scientists have supposedly demonstrated that the universe is much older than the Bible teaches. The first chapter of Genesis clearly teaches that God created all things in six days ("ordinary" days as defined by an evening and morning) and that human beings were created on the sixth day. This is confirmed and clarified in the other Scriptures as well (e.g., Exodus 20:8–11; Mark 10:6). And since the Bible records about four thousand years between Adam and Christ (Genesis 5:3–32), the biblical age of the universe is about 6,000 years. This stands in stark contrast with the generally accepted secular age estimate of 4.6 billion years for the earth, and three times longer still, 13.7 billion years, for the universe beyond. This fundamental time discrepancy is no small matter. It is obvious that if the secular age estimate is correct, then the Bible is in error and cannot be trusted. Conversely, if the Bible really is what it claims to be, the authoritative Word of God (2 Timothy 3:16), then something is seriously wrong with the secular estimates for the age of the universe. Since the secular time scale challenges the authority of Scripture, Christians must be ready to give an answer—a defense of the biblical time scale (1 Peter 3:15).
The Assumptions of Age Estimates
Why such a difference? What is really going on here? It turns out that all secular age estimates are based on two fundamental (and questionable) assumptions. These are naturalism (the belief that nature is all there is), and uniformitarianism (the belief that present rates and conditions are generally representative of past rates and conditions).
In order to estimate the age of something (whose age is not known historically), we must have information about how the thing came to be, and how it has changed over time. Secular scientists assume that the earth and universe were not created supernaturally (the assumption of naturalism), and that they generally change in the slow-and-gradual way that we see today (the assumption of uniformitarianism). If these starting assumptions are not correct, then there is no reason to trust the resulting age estimates.
[Read the rest of the article at Answers in Genesis.]