I challenge you to “Google” what “time” is. You will find thousands of words, but no information. The reason for this is no one knows what “time” really is. We all live in it and experience it, but it remains a complete mystery.
A prominent author recently defined time as “the measure of motion”. It is hard to imagine time without motion, but it must be more than that. Einstein showed us time is relative (probably to speed and location). I’ve thought of time as “the measure of increasing entropy”, but the Bible tells us before sin, there was no movement toward randomization. There was no aging, death, rust, deterioration; nothing wore-out … until Adam and Eve sinned. Then God cursed the Earth (Gen 3:17) and time changed. Then it became (as it is now) a measure of things moving toward an increasing state of randomness.
Thankfully, time will again change.
“For even the whole creation (all nature) waits expectantly and longs earnestly for God’s sons to be made known – waits for the revealing, the disclosing of their sonship. For creation (nature) itself will be set free from its bondage to decay and corruption into the glorious freedom of God’s children. We know that the whole creation has been moaning together in the pains of labor until now”. (Romans 8:19-22).
There is an important impact of not knowing what time is. Since we don’t understand time, we don’t really know what “age” is. Currently, we measure age as the sum of so many rotations of the earth. But, scientists tell us the earth is slowing down (albeit very little). This means every day is slightly longer than the one before.
If you have ever spun a top, you know the initial speed causes fast rotations in the beginning, but after a while it gets slower and slower. When the earth started spinning, its speed would have made those days much shorter than they are now. Perhaps that is the reason of the recorded high ages of the people living in the time described by the Book of Genesis.
The stunning extension of not understanding age comes about when scientists attempt to date the age of fossils or for that matter the earth.
The most common atomic dating methods use a ratio of one radioactive isotope relative to a certain other one. The ratios are assumed to be “set” in a specific way at the time the item was created (which is a big assumption since God may have created things with any ratio of isotopes He wanted). The methods then measure that particular ratio in today’s definition of days and extrapolate backward the number of today’s days to determine how old the item is predicted to be. Clearly, since historical days are not like today’s days, the extrapolation cannot be accurate.
But an even more important consideration is that because time was different before the first sin, physics was likely different, so radioactive decay (if there even was any) was probably also different. Physics then is not certain, but physics will again be changed after the New Heaven and New Earth is created by God because there will be no oceans or sun and people will live forever.
“And the city has no need of sun nor moon to give light to it, for the splendor and radiance of God illuminate it, and the Lamb is its lamp. The nations shall walk by its light and the rulers of the earth shall bring into it their glory, and the gates shall never be closed by day, and there shall be no night there.” (Rev 21: 24 – 25)
In conclusion, be wary of any type of dating of the earth, fossils, or anything else, for ALL methods are based on so many assumptions no one can accurately determine the age of God’s creation.