mortal sin

mortal sin (countable and uncountable, plural mortal sins)

1. (Roman Catholicism, theology) A sin which causes the loss of God's grace, leading to eternal damnation, unless the sinner repents, which includes their intent to confess and atone; such a sin is defined as a grave transgression against one of the Ten Commandments with the full knowledge and deliberate consent of the sinner.

   Antonym: venial sin

   Hyponym: grave sin

• Note that Catholic doctrine defines the Ten Commandments in a wider than literal sense. For example, thou shalt not commit adultery is taken to include all disallowed sexual activity; thou shalt not murder is taken to include any unnecessary, dangerous harm against a person's health and honor.

• deadly sin (strictly a different concept, though often used interchangeably)
• capital vice
• cardinal sin
• state of grace

• mortal sin on Wikipedia.Wikipedia

• normalist, stromalin