In general, you need to check your sources when someone tells you something that sounds questionable. OP, while this was embarrassing and Dad was wrong to bullshit a trusting child; ultimately this could be a valuable life lesson for you. If it sounds questionable, do your research before repeating it. That applies to anything... And for God's sake, if/when you have children don't repeat Dad's failing of lying to children.

This sucks. No way can you check everything you ever learned. Your life is a lie.

I never understood why parents feel the need to lie to their kids for a giggle. My ex-sister-in-law that it was hilarious to teach her daughter the wrong words for things when she was a toddler. “Lamp” for “table”, that sort of thing. But you now live in a time where basic info is at your fingertips. Wikipedia can at least tell you the basic story of Robin Hood. Look things up before you start spouting off nonsense.

And that's why it's important to tell your children about Santa Claus; so they can discover that even parents can lie.

wait. Wait wait wait. "I was so cocksure"??? Edit I had to look it up. Never heard that reference. I get it but .... I was cocksure it was not a word.

What part of the Bible did you think he was in? Was he hanging with Moses before God passed down the Ten Commandments? Did he manage to sneak onto Noah's Ark? Is the story of David and Goliath a lie and it was really Robin Hood who downed Goliath with an arrow? Or was he one of the other dudes that was crucified with J-Dog? I need answers, Robdamnit!