Evolutionists, atheistic and theistic, use the phrase "the present is the key to the past." In other words, they say that the way to understand the past is to observe what happens in the present. For instance, they say that since fossils form rarely in todays world, the vast layers of rock containing billions of fossils over most of the earths surface must have taken millions of years. Evolutionists tell us that since we observe mutations (that is, accidental changes in our genes) occurring today, these must have occurred ever since the dawn of time. Thus, mutations must be one of the mechanisms involved in the postulated evolutionary progression.

The Bible, on the other hand, tells us that there was a time when there was no sin, and thus there was neither animal nor human death, nor disease, nor mistakes. Mutations are mistakes that occur in our genes, and they are virtually all harmful. Those who believe in evolution have to assume that evolution is occurring today to be able to say that what we see today are the same processes that have gone on for millions of years. Thus, to be consistent, the Christian who believes in evolution should also believe that man is still evolving today.

How can we establish beyond doubt the details of an event that supposedly happened in the past? One way is to find witnesses who were there, or look for records written by witnesses. Therefore, the only way we can ever know for sure exactly what happened in the geological past is if there was someone who was there at the time (a witness) who could tell us whether geological processes have always been the same or whether at some time geological processes have been different. The Bible claims to be the record of One (God) who not only knows everything, but who has always been there because He is outside of time. In fact, He created time. The Bible claims that God moved men through His Spirit to write down His words, and that they are not just the words of men but the Word of God (1 Thess. 2:13, 2 Pet. 1:20–21). The Book of Genesis claims to be the records from God telling us of the events of creation and of other events in this worlds early history which have great bearing upon our present circumstances. Thus, the present is not the key to the past. Rather, revelation is the key to the past.