Not quite the same, but my Sunday school teacher, who was also one of my parent's best friends, was my secondary school English teacher. I was always nervous when I got a bad grade in my class, or stepped out of line he'd go tell them. To his credit, he never did, he also didn't treat me any different to all the other kids in the class. When in church, he was back to being "parent's friend mode". Good guy, he was a mentor to me outside of school and I miss him.