CHAPTER II
THE GRAVITY OF SIN
I. WITH reference to the gravity of its malice, sin is divided into mortal and venial. Holy Scripture teaches us that there are certain sins which exclude from the kingdom of God, [1] and, on the other hand, that the just, even while they remain just, frequently fall into slight faults. [2] The same truth is taught by the Church. [3] There are, then, mortal and venial sins.
The essence of mortal sin consists in turning aside from God, our last end, and virtually placing our supreme happiness in some created good. But our last end is the vital and guiding principle of moral conduct, and to throw that aside is to make complete shipwreck of the moral life. It is not merely to wander out of the direct path, as is done by committing venial sin; however much this is done, if the ship be kept moving toward the port, it will come to harbour at last; but if the ship be steered altogether away from the port, it will never get there. By committing mortal sin, then, we turn away from God, our last end; we rob our souls of the sanctifying grace of God which is their life, and we incur liability to eternal separation from God and punishment in hell. Venial sin is indeed an offence against God, but it does not turn the soul away from him, nor rob it of his sanctifying grace; and it is more easily pardoned than mortal sin.
2. Mortal sin is sin in the fullest and most complete sense; it is an act of consummate wickedness. A bad act must have three conditions in order to be mortally sinful:
(a) There must be full advertence to the grave malice of the act. A child that has not yet attained the full use of reason, a person half asleep, or half drunk, or half-witted, cannot know and appreciate sufficiently the malice of mortal sin, and so cannot commit it. It is not, however, necessary to reflect explicitly on God; or on the grave wickedness contained in the act in order to sin mortally. It will be sufficient if one who has the full use of reason consciously does what
