Why Young Earth

In recent years, as naturalism has continued its march into every crevasse of life, the crazy idiots who believe in a literal six day creation have become nearly extinct. Yet some still claim that the Young Earth model of creation is not only probable, but is the only view that is consistent with Christianity and Science. Why? What is the big deal? And what does it matter?
It might be profitable to look back at history, why did mainstream Christians change from a Young Earth model to the Old Earth model. Until Darwin popularized the theory of evolution (and yes, it is and remains a theory, not a scientific fact) very few scientist or theologians held that the earth was more than several thousand years old. Most Christians accepted that the earth was between ten and six thousand years old; there was no reason to suspect or postulate otherwise, six thousand years was approximately the figure arrived at by adding up the genealogies in the Bible and matching them with when certain events occurred. Evolution however, required many, many years. First they claimed they needed a few million.
Then they learned that the cell was more complex than they thought, and they simultaneously discovered that the earth was a few million years older than they had thought. And so the process continued until today with some naturalist claiming the earth is many billions of years old. They then turned to Christians and claimed that they were 'superstitious' because they did not accept that the earth is millions or billions of years old (This depends upon what dating method you use. If you age a sample with four different methods you often end up with four radically different ages). Their reasoning looks something like this:
Evolution is true
Evolution requires that the Earth is millions of years old
Therefore, the earth is millions of years old.

Christianity and other religions claim the years is not millions of years old
We know that the earth is millions of years old,
Therefore, we know Christianity and other religions are not true
If Christianity and all other religions are not true
Then they cannot challenge Evolution
If Evolution cannot be challenged
Then Evolution is True.
Just a hint for those of you who have not taken Logic 101, when your conclusion and your first proposition are one and the same you have what is called a circular argument, i.e. one that is false.
Christians employed three strategies in response to the charge that a literal creation is absurd because naturalists say so. The first stratagem is to simply accept what science is saying and reject Christianity. The second stratagem is to believe that the scientists have got it wrong (something not unheard of), and the bible has it right when it says day. The second stratagem is to try and fit the millions or billions of years into Genesis, and the most common way of doing that is to say that each 'day' in Genesis represents an age.
There are, however, many problems with doing this. The first is that the Hebrew word Yom used in Genesis means 24 hour day. Yom Kippur is the 'Day of Atonement', not the age, millennium, epoch, or era of atonement. Everywhere in the bible the word Yom is used with a number, or the phrase 'evening and morning' it means a literal 24 hour day. Many try to say that in English we often use 'day' to mean an age: the day of the Lord, In my grandfather's day, etc. We often say the dawn of an age, or the evening of an era. But do we ever say things like 'I remember how my father grew up in the morning of the first day of my grandfather' when we intend day to mean era? I don't. Maybe you do.
That is in English, here we are dealing with Hebrew, where Yom means 24 hour day.
Perhaps the single most important problem with the Old Earth view point is that it requires death before the fall in direct contradiction of Romans 5:12 “Therefore, just as sin entered the world through one man, and death through sin, and in this way death came to all men, because all sinned...” If death, pain, and suffering were built into the world by an all powerful, intelligent being working from outside time and space, how can such a god be called Holy?
In the end, we should not be asking ourselves 'why young earth?” but rather “why old earth?” Many have adopted the old earth viewpoint in order to appear scholarly and intellectual, but they are disliked by both sides, and atheists mock them for being unable to interpret their own Bible. Look at what the bible has to say about creation and the fall, there is no better interpreter of the Bible than the Bible itself.