A missionary is sent into deepest darkest depths of Africa to live with a tribe. He spends years with the people, teaching them to read, write and good Christian values. One thing he particularly stresses is the evil of sexual sin. "Thou must not commit adultery or fornication!"
One day the wife of one of the Tribe's noblemen gives birth to a white baby. The village is shocked and the chief is sent by his people to talk with the missionary.
"You have taught us of the evils of sexual sin, yet here a black woman gives birth to a white child. You are the only white man who has ever set foot in our village. Anyone can see what's going on here!"
The missionary replies, "No, no, my good man. You are mistaken. What you have here is a natural occurrence - what is called an albino. Look to thy yonder field. See a field of white sheep, and yet amongst them is one black one. Nature does this on occasion."
The chief pauses for a moment then says, "Tell you what, you don't say anything about the sheep, I won't say anything about the white baby."