St. Augustine pointed out that the sin of Adam was not simple disobedience, but the even more radical sin of disbelief. Adam and Eve did not believe the words of God when God said to them "From the tree of the knowledge of good and evil...you shall not eat; the moment you eat from it you are surely doomed to die." (Gen.2:17) Adam and Eve refused to believe that there could really be any such severe penalty for sin. And tremendous numbers of people ever since have done exactly the same thing: fall not just into disobedience, but also into disbelief. In their case, into disbelief that Hell can possibly be the penalty for any sin they have committed or might commit.
But there is another way in which the sin of Adam and Eve is the direct ancestor of cold-blooded, deadly sins ever since. St. John Chrysostom describes it. "The greatest of evils...had their entering in from pride....The first man, puffed up by the Devil...was made an example of, and became mortal, for expecting to become a god, he lost even what he had." (Homilies on Matthew, homily 15,sec.3).
Adam and Eve not only disbelieved God's stern warning; they believed the Devil who taught them that God was shamefully trying to keep them in subjection. They believed that by eating the forbidden fruit, they would become "like gods, knowing good and evil." (Gen.3:5), would "gain wisdom" (Gen.3;6) in the sense of divine wisdom. Their sin was not just disbelief. It was pride, the massive pride involved in thinking that one can gain wisdom so as to be equal to God, coming to know good and evil in the way that God Himself knows good and evil.
What can this possibly mean? How can human beings expect to know good and evil as God knows it? In two ways, really. First, to think that one knows so much about good and evil that one can safely ignore God's Commandments as superfluous and unnecessary, and make up one's own commandments, moral laws, for oneself. Second, to think that one now has a mandate on earth not only to learn as much as possible about what is good, but to learn as much as possible about what is evil.
And in this sense, we can see that those who choose to disobey the laws of God, very often follow Adam and Eve in their way of doing it. They not only fall into disbelief in God's warnings about a coming Judgment and about a coming eternal Hell for those who die unrepentant in sin. They, willfully blind to the horror of what they are doing, make themselves in their own minds into gods, into legislators of moral law at least for themselves, and into thinking that they have a mandate to learn about and investigate all evil, all places of debauchery, all debauched literature and entertainment. Pride. Tremendous pride. The same mad pride that was the root of the sin of Adam and Eve.
Those who have turned away from the laws of God often like to think of themselves as great explorers, as forging new ideas about right and wrong, as venturers into the study of all evil. They are not explorers, but merely part of a thronging mass of people following in the footsteps of Adam and Eve.
Salvation requires humility, humility before God and in the worship of God, in the commitment to the observance of God's Commandments, and in the realization that some kinds of knowledge, knowledge of evil, are better avoided as much as possible.