justice. 14 It is precisely this absence or privation of the original justice due which constitutes original sin in us. 15 The lack of original justice due is its formal element. The obligation of possessing it constitutes the material element. 16
Adam’s sin severed the supernatural bond between God and man by depriving man of sanctifying grace. It likewise deprived him of the concomitant gift of integrity or primordial rectitude which had kept the lower appetites of the body under control of the will. Man is now inordinately drawn to the gratification of his lower nature and away from God. This deordination found in our nature as a consequence of original sin we call concupiscence. It is the tendency of the sentient appetite and the passions to go out to sensible good before and in spite of the judgment of reason.
Following St. Augustine, 17 many of the Fathers and scholastic doctors placed the nature of original sin in inherited concupiscence. According to them, the loss of original justice involved also a permanent corruption of our nature, an infected condition of sin-stained flesh. In proof they quoted the Apostle’s letter to the Romans: "I see another law in my members, warring against the law of my mind and making me prisoner to the law of sin that is in my members.” 18 Original sin is thus virtually found in the infected human body. It is communicated through the natural act of generation. At the moment of union of the body with the created soul the inherited taint is communicated to the soul by reason of the essential unity of their nature.
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