Do you go to hell for missing Mass on Sunday?

When I was in grade school during the early 1960s the nuns told us that if we missed Mass on Sunday we would go to hell. Is that still the Catholic position? If not, when did it change? If it changed, what happened to the people who went to hell for missing Mass before they changed the rule? Were they able to get out of hell?
Where do the church fathers get the authority to make new sins that are not mentioned in the Bible?

The following link should assist you in better understanding the Catholic Church’s teaching on missing Sunday Mass. If you have any further questions or concerns that are not answered by these links, please contact Catholic Answers directly.

Recommended Reading:
Is it a mortal sin to miss mass on Sunday?

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