Three blonde guys are stranded on one side of a wide river and don't know how to get across.
The first blonde guy prays to God to make him smart enough to think of a way to cross the river. God turns him into a brown haired man, and he swam across.
The second blonde guy prays to God to make him even smarter, so he can think of a better way to cross the river. God turns him into a red-haired man and he builds a boat and rows across.
The third blonde guy prays to God to make him the smartest of all, so God turns him into a woman and he walks across the bridge.