Sin sets itself against God’s love for us, and turns our hearts away from God. However, because venial sins are of lesser gravity, they do not result in total separation from God. Although, a venial sin is not deadly in itself, it is still quite dangerous. 

On the other hand, mortal sins are grievous offences against God, kill the soul, and deserve hell. A mortal sin destroys charity in the heart of man by grave violation of God’s law. It is among this set of sins that we find the ones crying to God for vengeance.

Not only are they grievous offences and deserving of hell, but they are serious enough to kill the life of grace in us. 

They are intrinsically evil and very grave offences because they are always committed against the defenseless and vulnerable person.

Such sins are so deadly that not only do they cause exclusion from God’s kingdom but discomfort Heaven and the maker of heaven and earth until he avenges the soul of the deprived.