"When the woman saw that the fruit of the tree was good for food and pleasing to the eye, and also desirable for gaining wisdom, she took some and ate it. She also gave some to her husband, who was with her, and he ate it" (Gen. 3:6).
Paul, in Romans, affirms that all mankind is naturally under the guilt and power of sin, the reign of death, and the inescapable wrath of God (Rom. 3:9, 19; 5:17, 21; 1:18-19; cf. the whole section, 1:18-3:20). He traces this back to the sin of the one man whom, when speaking at Athens, he described as our common ancestor (Rom. 5:12-14; Acts 17:26; cf. 1 Cor. 15:22). This is authoritative apostolic interpretation of the history recorded in Genesis 3, where we find the account of the Fall, the original human lapse from God and godliness into sin and lostness. The main points in that history, as seen through the lens of Paul's interpretation, are as follows:
(a) God made the first man the representative for all his posterity, just as he was to make Jesus Christ the representative for all God's elect (Rom. 5:15-19 with 8:29-30; 9:22-26). In each case the representative was to involve those whom he represented in the fruits of his personal action, whether for good or ill, just as a national leader involves his people in the consequences of his action when, for instance, he declares war. This divinely chosen arrangement, whereby Adam would determine the destiny of his descendants, has been called the covenant of works, though this is not a biblical phrase.
(b) God set the first man in a state of happiness and promised to continue this to him and his posterity after him if he showed fidelity by a course of perfect positive obedience and specifically by not eating from a tree described as the tree of the knowledge of good and evil. It would seem that the tree bore this name because the issue was whether Adam would let God tell him what was good and bad for him or would seek to decide that for himself, in disregard of what God had said. By eating from this tree Adam would, in effect, be claiming that he could know and decide what was good and evil for him without any reference to God.
(c) Adam, led by Eve, who was herself led by the serpent (Satan in disguise: 2 Cor. 11:3 with v. 14; Rev. 12:9), defied God by eating the forbidden fruit. The results were that, first, the anti-God, self-aggrandizing mindset expressed in Adam's sin became part of him and of the moral nature that he passed on to his descendants (Gen. 6:5; Rom. 3:9-20). Second, Adam and Eve found themselves gripped by a sense of pollution and guilt that made them ashamed and fearful before Godâ€”with good reason. Third, they were cursed with expectations of pain and death, and they were expelled from Eden. At the same time, however, God began to show them saving mercy; he made them skin garments to cover their nakedness, and he promised that the woman's seed would one day break the serpent's head. This foreshadowed Christ.
Though telling the story in a somewhat figurative style, Genesis asks us to read it as history; in Genesis, Adam is linked to the patriarchs and with them to the rest of mankind by genealogy (chs. 5, 10, 11), which makes him as much a part of space-time history as were Abraham, Isaac, and Jacob. All the book's main characters after Adam, except Joseph, are shown as sinners in one way or another, and the death of Joseph, like the death of almost everyone else in the story, is carefully recorded (Gen. 50:22-26); Paul's statement "In Adam all die" (1 Cor. 15:22) only makes explicit what Genesis already clearly implies.
It may fairly be claimed that the Fall narrative gives the only convincing explanation of the perversity of human nature that the world has ever seen. Pascal said that the doctrine of original sin seems an offense to reason, but once accepted it makes total sense of the entire human condition. He was right, and the same thing may and should be said of the Fall narrative itself.
(from Concise Theology)