Eternity and forever are terms that our human minds often cannot grasp.
I was one told a story that put eternity in perspective. That story was... If a dove came down from heaven just once a year and took away one grain of sand and one drop of water, when this entire earth had been carried away, eternity WILL HAVE JUST BEGUN! Think about it!
God is real. I experience Him every day of my life and have a very intimate relationship with Him. He is as close to me as a relative or friend would be to you. Telling me that He does not exist would be like me telling you that your friend / relative does not exist simply because I have never met them.
For those of you who don't believe in God, or the Bible to be true, I would say this...If at the end of this life I find out that God does not exist, the Bible was just a hoax and it was all just indeed the greatest story ever told, I will have not lost anything and maybe have even gained something. However, if you find out that God is real and the Bible is so, you will have lost it all for eternity. There will be NO DO OVERS or second chances.
Every decade or so things (hairstyles, clothing, automobiles, music, electronics, etc.) change. Well, in the past societies have tried to burn or ban the Bible and say that God does not exist. However, God and the Bible are still here and going strong. If there were no substance or foundation to either, both would have faded long ago just as the styles mentioned above.
Have you ever royally screwed up and said "Man, I'm glad I got out of that one! I'll never catch myself in that situation again." Well, in the case of you finding out at the end of your life that God is real when you said He wasn't, it will be to late to make it right.
DON'T TAKE THAT CHANCE! Don't risk leaving this world without knowing Jesus as your Savior, for to do so would mean spending eternity lost in everlasting damnation.