I personally heard this illustration from evangelist Ron Comfort…

Once upon a time, an atheist scientist discovered that there was ‘lost time’ in the cosmic record. Through some unspecified process he learns that several hours have just gone missing. His Christian friend told him he would discover the reason for the lost time in the Bible. After reading the stories of Joshua and Hezekiah the atheist realizes that the Bible is true. He falls to his knees and is gloriously saved.

Well…you guessed it. It’s just not so.

Regardless of the amount of time involved, the discovery of a “missing” period of time remains implausible. If the sun had indeed stood still for a day a few millennia ago, we would have no way of determining that fact through astronomic observations today. We have no frame of reference, no “cosmic calendar” or “master clock” to check against to see if we’re overdrawn at the Bank of Time. The concept described here would be like giving someone a non-functioning clock and asking him to determine how much time had elapsed since the clock had stopped running. One could note the positions of the hands on the dial and make a reasonable guess about what the time of day was when the clock stopped running, but without knowing whether that time was A.M. or P.M., and without knowing the calendar date on which stoppage occurred, one could not possibly make any reasonable estimate about how long ago the clock stopped.

http://www.snopes.com/religion/lostday.asp