Whether sin causes a stain on the soul?

❌ Objection 1 : It would seem that sin causes no stain on the soul. For a higher nature cannot be defiled by contact with a lower nature: hence the sun's ray is not defiled by contact with tainted bodies, as Augustine says (Contra Quinque Haereses v). Now the human soul is of a much higher nature than mutable things, to which it turns by sinning. Therefore it does not contract a stain from them by sinning.

❌ Objection 2 : Further, sin is chiefly in the will, as stated above (Question [74], Articles [1],2). Now the will is in the reason, as stated in De Anima iii, text. 42. But the reason or intellect is not stained by considering anything whatever; rather indeed is it perfected thereby. Therefore neither is the will stained by sin.

❌ Objection 3 : Further, if sin causes a stain, this stain is either something positive, or a pure privation. If it be something positive, it can only be either a disposition or a habit: for it seems that nothing else can be caused by an act. But it is neither disposition nor habit: for it happens that a stain remains even after the removal of a disposition or habit; for instance, in a man who after committing a mortal sin of prodigality, is so changed as to fall into a sin of the opposite vice. Therefore the stain does not denote anything positive in the soul. Again, neither is it a pure privation. Because all sins agree on the part of aversion and privation of grace: and so it would follow that there is but one stain caused by all sins. Therefore the stain is not the effect of sin.