Chapter 6: Of the Fall of Man, of Sin, and of the Punishment Thereof
(Parts Three & Four)
Adam and Eve’s sin affected not only them; it affects all their posterity. Adam was (as explained in Romans 5:12-21) the federal representative for all mankind. Because all we who, though not yet even conceived, were “in him,” when he sinned, we sinned. Proof? Death has reigned ever since, just as God promised.
The cry of the natural man is almost always, “That’s not fair.” But think about it. Aren’t their countless decisions made by others, over which we have no control, that affect us? The president declares war, and whether we are for it or against it, we are at war. Parents move due to a job change, and whether the children like it or not, they are uprooted and resettled into another town. Examples could go on and on. The point is, as our federal representative, Adam’s sin is our sin as well.
For those who insist that they want to be judged for their own lives, not the life of Adam, our sins only confirm our sinfulness and validate God’s just judgment. So even if we were not guilty in Adam (which we are) we are no less off the hook.
One more thing: If we reject the concept of a federal head standing in the place of those he represents, we must also reject Christ as the Federal Head over all who are saved. Just as Adam’s sin condemns all who are “in him,” Christ’s righteousness saves all who are “in Him.” Are people are “in Adam.” The question is, are you “in Christ”?
Jesus said we must be perfect even as our Father in Heaven is perfect.  We not only do not do anything perfectly, Adam’s sin has corrupted all mankind, rendering us incapable of doing anything (much less everything) perfectly.
Because we are born into this condition, the Bible says we are by nature children of wrath  and servants of sin, the subjects of death.  Because (a) we are sinners by nature, (b) we commit sins, not the other way around. Stated another way, we are not sinners because we sin; we sin because we are sinners.
Even after we are born again, given new hearts, and made new people,  vestiges of the corruption of the Adamic nature remains until we are glorified and in Heaven, where there is no more temptation or sin—at all.
In the mean time, let us put off the old man and put on the new man, growing in sanctification, looking forward longingly to that great day of glorification.
 Mat 5:48,  Eph 2:3,  Rom 6:20; 5:12.  2 Cor 5:17.