Historically speaking, both Roman Catholicism and Protestantism have understood that there are degrees of sin. The Roman Catholic church makes a distinction between mortal and venial sin. The point of that distinction is that there are some sins so gross, heinous, and serious that the actual commission of those sins is mortal in the sense that it kills the grace of justification that resides in the soul of the believer. In their theology, not every sin is devastating to that degree. There are some real sins that are venial sins. These are less serious sins in terms of their consequences, but they don’t have the justification-killing capacity that mortal sins have.
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