Article 2. The Effects Of Sanctifying Grace
We shall better understand the nature of sanctifying grace by studying what are known as its “formal effects.” As the _causa efficiens_ of a thing is commonly farther removed from our mental grasp than its effects, we are ordinarily more familiar with the latter than with the former. For this reason the glories of divine grace can be best explained to children and to the faithful in general by describing the effects it produces in the soul.(1050)
1. SANCTITY.—The first among the formal effects of sanctifying grace (an effect connoted by its very name) is sanctity. Eph. IV, 24: “Put on the new man, who according to God is created in justice and holiness of truth.”(1051) The Tridentine Council explicitly mentions sanctity as an effect of sanctifying grace: “Justification ... is not remission of sins merely, but also the sanctification and renewal of the inward man through the voluntary reception of the grace and of the gifts whereby man from unjust becomes just.”(1052) It follows that the two elements of active justification, _viz._: remission of sin and sanctification, are also constitutive elements of habitual or sanctifying grace. For it is precisely by the infusion of sanctifying grace that sin is wiped out and sanctity established in its place.(1053)
a) By sanctifying grace the justified man becomes a living member (_membrum vivum_) of the mystical body of Christ. His sins, it is true, did not forfeit membership in the Church, so long as he preserved the faith, but by sinning he became a dead member who can regain life only by returning to the state of grace. Grace is the life of the soul, sin its death. Hence the evil of mortal sin can be most effectively illustrated by contrast with the glory of divine grace, and _vice versa_. Cfr. Gal. II, 20: “And I live, now not I, but Christ liveth in me.”(1054)
b) He who hates mortal sin and faithfully obeys the will of God, enjoys peace of heart,(1055) whereas the sinner is incessantly harassed by qualms of conscience. The faithful Christian rejoices in serving His Master and combats the flesh, the world, and the devil with a fortitude that not infrequently rises to heroic proportions, as the example of many holy men and women proves.