Why does the world think Christians are foolish for giving up worldly pleasures?
The world thinks believers are foolish because it cannot comprehend the glory awaiting them. It sees only that Christians shun some earthly pleasures for a few years, not the immeasurable ratio between seventy years and unlimited billions of years in eternity. That eternal perspective is beyond the world's comprehension, so it labels them kooks.
Les explains that the world sees believers as a bunch of kooks because they shun some of the pleasures of this world for a few years. They have no concept of the ratio: what is seventy years compared to unlimited billions of years? It cannot even be put into a mathematical ratio, and this is what they cannot comprehend. Paul speaks of that which prepares us for that kind of eternity through the Gospel he preached, by which you are saved, but you must know what you believe.