Institutes of the Christian Religion by John Calvin.
Book 2: Of the knowledge of God the Redeemer, in Christ, as first manifested to the fathers, under the law, and thereafter to us under the gospel.
Chapter 1: “Through Fall of Adam, the Human Race Made Accursed”
Section 8: Defining original sin, Calvin states that it is “a hereditary corruption and depravity of our nature, extending to all the parts of the soul, which first makes us obnoxious to the wrath of God, and then produces in us works which in Scripture are termed works of the flesh.” The works of the flesh are “sexual immorality, impurity, sensuality, idolatry, sorcery, enmity, strife, jealousy, fits of anger, rivalries, dissensions, divisions, envy, drunkenness, orgies, and things like these” (Gal 5:19-21). From this we have two observations: First, in that we are so corrupted in our nature, it is no wonder that we are condemned by God. Despite the fact that this sin in our lives is present because of Adam’s sin, we are held accountable for the sins that we commit and everyone, everywhere, has sinned against God (Rom 5:12). It is this “seed” of sin that makes us sinful and that is why even a baby, who is unable to willfully sin against God is seen as one who has already done so. Second, our inherent sinfulness continues to produce new sins within us, despite our desires to stop them. Whether in thought, careless word, or deed, we continue to sin. We can thus conclude that our whole person, from our thought life to our words and actions are dripping with the sin that keeps us from our God.
Section 9: In this section the author continues to push the issue that we are wholly corrupted, in every part of our bodies and in the deepest recesses of our soul. Stating that Romans 3 merely describes original sin as being one with our nature, he continues to show in Ephesians (Eph 4:17-18, 23-24) that our regeneration through Christ applies not to just our soul but to our whole body, and that we will be transformed by the renewing of our minds (Rom 12:2). Therefore, because so great a transformation is necessary for us to be approved by God a restoration of our whole body and soul is required. This cannot happen through mere works but requires God to act for us on our behalf. We cannot be the originators of this transformation since all of our pre-conversion thoughts and intentions are enmity against God (Rom 8:7).
Section 10: Do away with the people who blame God for our sin and our sin nature. Calvin explains that the idea that God is the author of sin and that He “could have provided better for our safety” by preventing Adam’s sin is absurd. Concluding this section, the author states, “Since man, by the kindness of God, was made upright, but by his own infatuation fell away unto vanity, his destruction is obviously attributable only to himself.”
Section 11: In conclusion of this chapter, it is evident that man is corrupted by a natural “viciousness”, but not one that comes from nature (that is, from our bodies) but from a corrupt spirit within our souls. This heredity of sin, then, keeps us from God and from seeking to honor Him with our lives since we are, after all, “by nature the children of wrath” (Eph 2:3). So, how is it that “good people” who seek to “do good” are seen as vile sinners before God? It’s not the work itself that brings the charge, but the corruption of the work. Our sinful souls, controlling sinful hands, cannot from themselves produce works that are clean before a holy and perfect God.