Do it, if you can Abraham

Genesis 15:5 - And He brought him forth abroad, and said, "Look now toward heaven, and tell the stars, if thou be able to number them."
And He said unto him, "So shall thy seed be."

There is an important pause here that merely looks like bad story telling when you read quickly.
I've inserted a line break to show the pause that indicates Abrahams obedience and reflection. He was given a command by God: consider, count, try.
And Abraham is completely unable to do it.

Now I think that the point of this passage is not on the number of offspring, but on his total inability to do the task. He flatly can't count that high and obey God. It's beyond him, above him, and God knows that. And in that way, that humble, hopeless way, his offspring shall come. Not by human ability, nor scheming, but by God's power. Abraham is being told of what is to come, not so much of how numerous his offspring would be, but of how the Messiah would come into the world, and into hearts. And once Abraham got that, once he pondered it and understood his helplessness, God told him the rest, "so shall thy Seed be."
 We are like Abraham in the same way that we can't do it. Justification is not by might nor by power, but by His Spirit. And once we understand that, we have Jesus right there to save us.