When you get really mad and you’re a good christian so you don’t want to have profane language.
(Someone steals yo girl) “Oh Darn Darn! I hope no one steals my girl again!”
you would use darny darn darn on a farm instead of god damn it.
John: "Can you please do my homework, Fred?"
Fred: "No, you can do it yourself."
John: "Oh darny darn darn on a farm."