This cartoon (one from a New Yorker of unknown date - H/T: Power Line) says all there is to say about original sin:
Without realizing it, the cartoon derives its cleverness from the very thing it is celebrating: original sin.
By proclaiming it as truly "original" (i.e., the distinctive product of Adam and Eve themselves, and also the very first of all human sins), it emphasizes how the first couple's first sin put man's choices before God's commands.
And in doing so, it perfectly -- but no doubt unwittingly, from the cartoonist's point of view -- illustrates that which it depicts.
A picture worth one thousand words.