When you look at the sun, you might imagine that you are seeing light that was emitted very close to the time you observe it. In fact, it takes light about 8 minutes to get from the Sun. That isn’t very long. But you may be more surprised to learn how long the light takes to get from the center of the Sun to the outside. Remember that we can measure both the nuclear reactions taking place in the center of the Sun using neutrinos, and we can also determine the density profile and temperature of the interior of the Sun by measuring the way the Sun vibrates, just like we can determine the density profile in the Earth using seismology, as we hunt for oil, etc. Using known laws of physics that predict exactly not only the density profile of the sun, and its temperature, and also the rate of nuclear reactions in the sun’s core, we find that it takes almost 1 million years for energy emitted in the center to make its way to the surface, where we can then see it!
The argument has employed secular assumptions to argue against the biblical timescale. This is a case of circular reasoning; the author has assumed the Bible is false in order to “prove” that it is false. In this case, the unbiblical assumption is naturalism, which has led to incorrect initial conditions. In other words, it is assumed that we know that the photons on the surface of the sun today actually were produced in the core by the same natural processes in which they are produced today.
When God created the sun, it was shining right away—not because the photons had taken a long time to travel from the core, but because God made the sun hot! Notice that God did not need to create the photons directly (out of nothing). Simply by God giving the sun a high temperature, photons are produced from the plasma.1 Today that temperature is maintained by nuclear fusion in the core. But there is no sound reason to assume that photons emitted from the surface of the sun were ever generated in the core. The Christian position is that the sun was created supernaturally by God. So, the secular assumption of naturalism is to blame for the inflated age-estimate.
If the Sun was 6000 years old, it would not be shining as it does. In fact, we can see stars that are just forming and are only thousands of years old, and exactly as we predict, they have not settled down to burn evenly and uniformly as our Sun does. If the Sun were only 6000 years old, its brightness would be such that life on Earth would be burnt to a crisp, and its brightness would also vary greatly over the course of human history.
Since nobody was around when the sun was created, how can we verify this? It is blindly assumed by those who reject biblical creation. Have you or anyone else ever observed a star form? It supposedly takes millions of years (in the secular model), so no one could actually observe it even in principle. Those who believe in the big bang and secular models of star formation have no observational evidence that these things have occurred nor is there any sort of recorded eyewitness account. However, Christians have a perfect Eyewitness and His recorded account.2