MonkeyRat Irons

I wanna get a tatoo on the inside of my bottom lip that reads “God” with a little cross, but my parents say (Christians) that if people get tatoos you go to hell! My sister’s boyfriend has a big giant tatoo on his left arm so is he going to hell?

Why are my parents saying this?

My parents are soo protective, I want to get a tatoo when im 16 this feb, or when im 17. How can I get my parents to agree with me getting a tatoo.

And any pics that can give me ideas if I get one anyways?
THANKS!