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Further discrepancies between Scripture and the gap theory are seen when looking at the law God gave Moses. As God etched the Ten Commandments in stone, He said, “For in six days the Lord made heaven and earth, the sea, and all that in them is” (Exodus 20:11). God unmistakably says that everything was made in six days. This would include angels, heaven, earth, and mankind—everything.

The difficulty here is, as SoSick pointed out, that a day to God is not the same as a day to Moses. God could be taking the days as Moses sees them as a symbol for the days as God sees them. So the Sabbath represents the time that God rested so man should take every seventh day off. This is obviously wise in that everyone needs some time to relieve stress. Additionally, Jesus said the Sabbath was made for man, not God.

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The gap theory also disagrees with New Testament Scripture. The Bible is clear that “by man came death” (1 Corinthians 15:21-22) and “by one man sin entered into the world, and death by sin” (Romans 5:12). These passages undeniably teach that the first sin came by Adam and that there was no death before sin. Therefore, it is incompatible to teach that a civilization existed before Adam, because it would place death before sin—a direct contradiction to Scripture.

There is another difficulty here in that we really don't know what "death" Paul is talking about. He was a scholar of the Torah so he must have been very familiar with the scriptures. See Genesis 2:16 and 2:17...

16And the Lord God commanded the man, saying, You may freely eat of every tree of the garden;
17But of the tree of the knowledge of good and evil and blessing and calamity you shall not eat, for in the day that you eat of it you shall surely die.

However, as we all know, Adam did not die on the day he ate of that tree. In fact, he did not die for over 900 years. Additionally, none of the curses that God puts in place in chapter 3 say anything about adding death to the world, just to humans.

So, what did God mean when he told Adam that he would die on the day that he ate the fruit? Is this a different kind of death than physical death? If it is death of the spirit, then physical death may have existed all along. Paul, in Romans 8, mentions that our spirit is dead unless we accept Christ which lends support to the "death" in Adam was spiritual death.

If a day for God is a long time and physical death is not the death initiated by Adam's sin, then the Earth could be very old and evolution is a possibility compatible with the Bible.

A faith that connot survive collision with the truth is not worth many regrets. -- Arthur C. Clarke