The quote isn't a biblical one, it was God's promise to Abraham that his descendants would be as numerous as the sand on the seashore. As far as evidence of a so called "higher being" goes, apart from the mind boggling complexities of the natural world, I believe it only comes from a personal experience, sitting around waiting will prove little. Karl Marx, who was an atheist said, if anything would convince me of the existence of God it would be the thumb" try doing anything without your thumbs for a while and you'll quickly discover what a brilliant design they are!