De Peccato Originali

Original sin standeth not in the following [imitatione] of Adam (as the Pelagians do vainly talk), but it is the fault and corruption of the nature [vitium et depravatio naturae] of every man that naturally is engendered of the offspring of Adam, whereby man is very far gone from original righteousness, and is of his own nature [natura] inclined to evil, so that the flesh [caro] lusteth [concupiscat] always contrary to the spirit [adversus spiritum]; and therefore in every person born into this world, it deserveth God's wrath and damnation.

What we are concerned with here is not merely a "lack" or a "privation" in our original righteousness, such that we individually re-capitulate Adam's fall. Rather, it is an infection in our very species-being, identified as a sensual lust of the flesh, which stands ever opposed to spirit.

And this infection of nature [haec naturae depravatio] doth remain, yea, in them that are regenerated, whereby the lust of the flesh [affectus carnis], called in Greek phronema sarkos (which some do expound the wisdom, some sensuality, some the affection [affectum], some the desire of the flesh [carnis]), is not subject to the law of God. And although there is no condemnation for them that believe and are baptized, yet the Apostle doth confess that concupiscence and lust [concupiscentiam] hath itself the nature [rationem] of sin.

Even baptismal rebirth cannot eliminate it and, hence, this inborn inclination of flesh, being contrary to the law of God, has the like character of sin (although it is unlike most sin, being an innate predisposition and not a conscious act of the will).

Neither the words nor the concept of "total depravity" appear here, nor a repudiation of Imago Dei, nor a denial of free will, or an endorsement of individual "pre-destination." Nor is there a disavowal of reason or spirit, only its constant opposition by the "knowing-how" of our flesh.

This is all much closer to Aquinas than Calvin, IMHO.

Afterwords: For the Romans, concupiscence is not sin but is "of sin and inclines to sin." For the Calvinists, it is "true and proper sin." What say we? It "hath itself the ratio of sin."