Matthew 24:22 says, " And except those days should be shortened, there should no flesh be saved: but for the elect's sake those days shall be shortened."   Consider the fact that God said that the Great Tribulation would be 1260 days, the puzzling question has always been, "Why would God, who is all knowing, change His mind?  He doesn't...He only shortens the daylight hours and nighttime hours.  Next question:  Why is there such a need?   Consider the conditions during those days when the whole of the heavens is moving out of it's normal oribt; What would the people on earth experience? It would be so hot that if the day-light hours were not shortened, no man could survive it.  The normal growing season to produce food is gone and with that comes starvation and all the slaughter that come with trying to get food and water.    I believe, that since it is the very condition that guides our 24 hour days now are suddenly changed, then it must also deal with the length of those days that will be altered.   Instead of 24-hr days, there will be probably 16 hour days.  Please watch this good teaching on that very fact.  Thanks!   gerlinda http://www.youtube.com/watch?v=kozgpEhcqGk&feature=related