Eternity doesn't exist outside of time. The Bible says He's eternal. He's not. His max age is the age of the universe. No I'm not saying He didn't always exist. Bit hard to explain because all words are time related.
It has to do with dimensions. With more than the 4 we know it's possible to stand outside time. There is only "now" and even that is a time indication.
Being outside of time isn't the same as eternal. imo....
Watch this movie how 3D is experienced in a 2D world: http://www.youtube.com/watch?v=BWyTxCsIXE4
More dimensions will do the same with time.
Imagine a narrow tube of billions of miles long. Somewhere near the start of that tube is a tiny window. Water flows trough that tube and you observe it until 14 billion gallons have passed your tiny window.
The water is time flowing by. It just goes in one direction.
People in flatland have 2 dimensions. They only have length and width.
We have 3 dimensions. Length, width, height. We can move forward and backward. Up and down.
We also know time, which usually is called the 4th dimension. But in a way it's 3.5 because we can't move backward in time or even just stand still.
We can just watch the water run through the tube. Constant speed. Always the same direction.
If we assume one gallon of water is a year, we watched 14 billion years.
However at the end of the tube the water flows into a huge lake. That lake is filled with 14 billion gallons of water = TIME
If you stand at the shore of the lake you see 14 billion gallons of water. You see 14 billion years.
You now observe 14 billion years in one look. When you take a boat you go to any point in time.
Or simply image the whole tube is transparent and the water doesn't flow out. You now can observe the whole tube. 14 billion years of time.
So if you walk around in your house you can't just walk between rooms but also the history of rooms. Yet time doesn't exist....
There are (likely) 10 dimensions. That means you are present is all places and time at the same time. Yet you aren't
The above isn't accurate but gives fair impression of the concept.
And even then things are based on how we extrapolate things from our experience. And that could very well be totally wrong