Mortal and Venial Sins
Roman Catholic theology distinguishes between mortal and venial sins. A mortal sin removes your justification, and if you die with unconfessed mortal sin on your soul, you will be sent to hell. Venial sins do not destroy your justification, and only reduce your rewards or add to your time in purgatory. The Reformation rejected this system because of its works- orientation, but did not reject the idea of degrees of sin. John Calvin said that all sin is mortal in the sense that it deserves death, but no sin is so severe that it can destroy the grace of justification.