Pascal’s Condom
Consider:
Either God exists, or he doesn’t.
If God exists, and you have a child, then that child will wind up either in Heaven or in Hell.
If God doesn’t exist, then your children won’t go to either.
Therefore, if God exists and you have children, then you risk letting a soul go to Hell for eternal torture.
Therefore, it’s best not to have children.
Surely deliberately taking the risk of sending a soul to eternal torment in a religion’s hell is in itself a heinous sin. Or even a mortal sin. So, by having children (who may or may not be going to hell, or heaven) you condemn yourself and any willing partners/ assistants/ facilitators to hell.
This question has already been asked, albeit in a different context: some denominations believe that people who have never heard of Jesus won’t be sent to hell because they’ve never been given the chance to accept or deny him. Hence, any missionary who teaches someone about Jesus but fails to convert him has just sent that person to hell. There’s a story about an Eskimo or someone asking a missionary these questions, and ends by asking, “So why did you tell me all this in the first place?”