“Your
dogma makes us strictly responsible for the fault of
Adam.” That is a misconception of our
doctrine.
Our dogma does not attribute to the children of Adam any properly so-called responsibility for the act of their father, nor do we say that original sin is
voluntary in the strict sense of the word. It is
true that, considered as “a
moral deformity”, “a separation from
God”, as “the death of the
soul”, original sin is a real
sin which deprives the
soul of
sanctifying grace.
It has the same claim to be a sin as has habitual sin, which is the state in which an adult is placed by a grave and personal fault, the “stain” which St. Thomas defines as "the privation of grace" (
I-II:109:7;
III:87:2, ad 3), and it is from this point of view that
baptism, putting an end to the privation of grace, “takes away all that is really and properly
sin”, for
concupiscence which remains “is not really and properly
sin”, although its transmission was equally
voluntary (Council of Trent, Sess. V, can. v.). Considered precisely as
voluntary, original sin is only the shadow of
sin properly so-called. According to
St. Thomas (In II Sent., dist. xxv, Q. i, a. 2, ad 2um), it is not called
sin in the same sense, but only in an analogous sense.
Several
theologians of the seventeenth and eighteenth centuries, neglecting the importance of the privation of grace in the explanation of original sin, and explaining it only by the participation we are supposed to have in the act of
Adam, exaggerate this participation. They exaggerate the
idea of
voluntary in original sin, thinking that it is the only way to explain how it is a
sin properly so-called. Their opinion, differing from that of St. Thomas, gave rise to uncalled-for and insoluble difficulties. At present it is altogether abandoned.
Hopefully you’ll read this before you reply to that one. 
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