I recently read this in an talk by Elder Maxwell. I am always amazed by his depth.
"Suppose, for instance, that we imagine a 'being' moving onto our earth whose entire life-span is only 1/100 of a second. Ten thousand 'years' for him, generation after generation, would be only one second of our time. Suppose this imaginary being comes up to a quiet pond in the forest where you are seated. You have just tossed in a rock and are watching the ripples. A leaf is fluttering from the sky and a bird is swooping over the water. He would find everything absolutely motionless. Looking at you, he would say: 'In all recorded history nothing has changed. My father and his father before him have seen that everything is absolutely still. This creature called man has never had a heartbeat and has never breathed. The water is standing in stationary waves as if someone had thrown a rock into it; it seems frozen. A leaf is suspended in the air, and a bird has stopped right over the middle of the pond. There is no movement. Gravity is suspended.' The concept of time in this imaginary being, so different from ours, would give him an entirely different perspective of what we call reality.
"On the other hand, picture another imaginary creature for whom one 'second' of his time is 10,000 years of our time. What would the pond be like to him? By the time he sat down beside it, taking 15,000 of our years to do so, the pond would have vanished. Individual human beings would be invisible, since our entire life-span would be only 1/100 of one of his 'seconds.' The surface of the earth would be undulating as mountains are built up and worn down. The forest would persist but a few minutes and then disappear. His concept of 'reality' would be much different than our own.
"That's the most clever way I have seen time and intimations of eternity dealt with. It is very important that we not assume the perspective of mortality in making the decisions that bear on eternity! We need the perspectives of the gospel to make decisions in the context of eternity. We need to understand we cannot do the Lord's work in the world's way."