Can a Christian believe the Earth is 4.5 billion years old or does the Bible say its 6000 years old?

On some topics, the Bible is extremely clear. For example, our moral obligations toward God and the method of salvation are discussed in detail. On other topics, the Bible doesn’t provide nearly as much information. Reading the Scriptures carefully, one finds that the more critical a topic is, the more directly the Bible addresses it. In other words, “the main things are the plain things.” One of the topics not explicitly addressed in Scripture is the age of the earth.

There are several ways of attempting to determine the age of the earth. Every method relies on certain assumptions which may or may not be accurate. All fall in a spectrum between biblical literalism and scientific literalism.

One method of determining the age of the earth assumes that the six days of creation presented in Genesis 1 were literal 24-hour periods and that there are no gaps in the chronology or genealogy of Genesis. The years listed in the genealogies of Genesis are then added to get an approximate time from creation to certain Old Testament figures. Using this method, we arrive at an age for the Earth of approximately 6,000 years. It’s important to realize that the Bible nowhere explicitly states the age of the earth — this is a calculated number.

In 1650 Archbishop James Ussher gave a biblical account of the age of the Earth, using an Old Testament period event that corresponded to a known historical date. The death of the Babylonian King Nebuchadnezzar in 562 BC. Then by adding up the generations of the prophets, patriarchs and the 139 genealogies of the Old Testament from Adam to Nebuchadnezzar, Ussher came to the conclusion the date of the Earth was October 22, 4004 BC at 6PM, which was a Saturday.

Another method of dating the Earth uses rock sediments of the planet, or “sedimentary sequences”. The problem with counting layers of sediment rock, is that sediments were thought to be 1000 years old per foot of sedimentary layers.

However, with catastrophic flooding events like Noah’s ark for example, these measurements changed to a foot of sediment every few days giving planetary dates ranging from 3 million to 15 billion years. Even the deepest layers of rocks are not the oldest things on earth, rocks cannot survive the violence of earths evolution over time.

Objects from space were the best calculation, fragments from an iron asteroid that made a crater in the Grand Canyon that later became Arizona, survived intact. Fragments from the asteroid on the earth would indicate the age of the solar system, including the earth. Picking a rock from this area reveals, that the rocks start out radioactive and experience multiple transmutations, until it becomes the stable atom of lead. Examining a section of the meteorite, while knowing the constant rate of uranium decay, you can determine the age of the meteor. Then by measuring the amount of lead in the meteor and you can learn the age of the Earth. At least this was the reasoning.

Clair Cameron Patterson dated the planet by using the mass spectrometer at the Argonne National Laboratory on an isolated segment of the iron-meteorite, he examined data on the uranium and lead isotopes in the meteorite. With the new data, in 1956 he published “Age of Meteorites and the Earth”, the first paper containing the true age of the solar system’s accretion, which was 4.550Gy ± 70My, which is to say the World is 4.55 billion years old.

The early conclusions that date the world as 4–6 thousand years was solely based on approximations using scripture, without considering the depth of the meaning of Genesis 1:1–2.

Man cannot know how long the Universe and the world has existed, before man was placed on the planet. Even the conclusion of science that the world is 4.55 billion years old, is guesswork, because the meteorite used to date the planet struck the earth which was already in existence in order for the meteor to hit the earth in the first place.

What we learned from sciences dating, was that a single meteor in the expanse of the Universe, which is riddled with planets, asteroids and meteors, was 4.55 billion years old, it could have been a baby in comparison to the true existence of the universe.

Another method of determining the age of the earth is to use resources such as radiometric (carbon) dating, geologic cycles, and so forth. By comparing different methods, and seeing if they align, scientists attempt to determine how old the planet is. This is the method used to arrive at an age for Earth of about 4 to 5 billion years. It’s important to realize that there is no means to directly measure the age of the earth — this is a calculated number.

Both of these methods of determining the age of the earth have potential drawbacks. There are theologians who do not believe that the Bible’s text requires the creation days to be literal 24-hour periods. Likewise, there are reasons to believe that the genealogies of Genesis have intentional gaps, only mentioning certain men in the lineage. Some measures of the age of Earth do not seem to support it being as young as 6,000 years, and denying such evidence requires the suggestion that God made virtually every aspect of the universe “appear” to be old, for some reason. Despite claims to the contrary, many Christians who hold to an old earth view take the Bible to be infallible and inspired, but they differ on the proper interpretation of a select few verses.

In more recent explorations, Göbekli Tepe (Turkish for “Belly Hill”) is an important archaeological site in modern Turkey that contains the world’s oldest known megaliths 12–15,000 years old. The hill is 1,000 feet in diameter and located at the high point of a mountain ridge in southeastern Turkey.

The discovery of Göbekli Tepe contradicts as aspect of Young earth creationism (YEC) which is the belief that the earth is relatively young. Young earth creationists usually place the age of the earth at 6,000 years (10,000 years being an upper limit).

Beyond other evidence of dinosaurs and other fossils dating back to millions of years, Göbekli Tepe as a civilization upends the young earth philosophy in the specific. Göbekli Tepe was built prior to Stonehenge, it is considered by some to be the world’s oldest known temple or religious site.

In short, there are ample reasons to believe that secular estimates for the age of the earth are inaccurate, as well. Relying on science to answer scientific questions is fine, but science cannot be treated as infallible.

In the end, the chronological age of the earth cannot be proven. Unfortunately, there are voices on both sides of the issue who claim theirs is the only possible interpretation — theologically or scientifically. In truth, there is no irreconcilable theological contradiction between Christianity and an old earth. Nor is there a true scientific contradiction in a young earth. Those who claim otherwise are creating division where none needs exist. Whichever view a person holds, what matters is whether or not he is trusting in God’s Word to be true and authoritative.