Unpardonable Sins as per Shiva Purana.

If one prays to Lord Shiva with utmost devotion then He will surely help his devotee. Anyone who commits these sins is not forgiven by Lord Shiva. As per Shiva purana, we definitely will reap for the wrong doing that we committed even without the knowledge of anyone.

The 12 unforgivable sins are listed below.

1. Showing interest in someone else’s spouse
2. The desire to loot others wealth.
3. Blaming and destroying others motive for Selfish reasons.
4. Continuous wrong doings or not performing any good deeds.
5. Abusing women while they are pregnant or menstruating.
6. Gossiping about other people.
7. Spreading rumours about other people.
8. Destroying or Killing someone by their Wrongdoings.
9. Consuming beef is said to be a sin in the Shiva Purana
10. Violence against women and Children is unjustifiable.
11. Persecution of Mother, Father, Teacher and Elders is a sin.
12. Erroneous accumulation of wealth and retrieving the given charity is a sin.