One of my favorite Bible stories is Noah's Ark and the Rainbow.
 You can read more about Noah in Genesis 6-9

I love this story for one main reason . . . no, it's not because of the awesome way God helped Noah and his sons (Shem, Ham and Japheth) build an ark that large (450 feet long, 75 feet high and 45 feet wide) ... not because it took 120 years to built the thing ... it's not how cool it was that God made all the animals meet up at the ark to get on board for Noah in just a weeks time (two of most animals and seven of some special ones) ... it wasn't because Noah was 600 years old when the flood came... even though it was totally amazing, it's not that the flood waters covered the entire earth (20 feet above the mountaintops, that's deep) ...

not even the fact that God helped Noah, his family and all those animals get along for so many months (they were on that boat for over a year!) ... Those are all really, really cool facts about Noah and the Ark, but what I like most about the story is . . . the RAINBOW I like the rainbow because of it's meaning. You see, after the flood, God decided He would never do it again. So He made the rainbow, put it in the sky and told Noah ... Genesis 9:11-16 NIrV "Here is my covenant (or, promise) that I am making with you. The waters of a flood will never destroy all life again. A flood will never destroy the earth again." And God continuted, "My covenant is between me and you and every living thing with you. 

It is a covenant for all time to come. Here is the sign of the covenant I am making: I have put My rainbow in the clouds. When the rainbow appears in the clouds, I will see it. I will remember that my covenant will last forever." HOW AWESOME!!

Not because Noah got to see the very first rainbow, but that God would make such a beautiful thing to remind Himself of such a loving promise. And as a reminder for us, too. It is a symbol of a promise that God will protect us. Now, I know what you're thinking . . . But there are floods all the time on the earth. Yea, but there never has been and never will be a flood like the one Noah went through.

God will never destroy the ENTIRE earth again with a flood. God promised to save us and the Earth from such a terrible PHYSICAL destruction. There's another symbol that remids us that God promises to save us from a SPIRITUAL destruction.

THAT'S THE CROSS!! Yea, the same one that Jesus, God's son, died on. Jesus died on that cross to pay for all our sins and to open the gate to Heaven for everyone who believes in Him, loves Him and asks Him into their heart.