To be born in sin is to say that I was born a stranger to myself, in a mask that hides me from God blinds me to the Truth and to His Will, and in this way I was born straddling the line between life and death, existence and non-existence. We are all born on the verge of a choice, and the span of our lives is the making of that choice and the concretizing of its consequences. If you are never anything more than what you were at birth, you might as well have never been born at all.
We all have a shadow that we carry with us everywhere. It is the false self that cannot release because we think that we are it, or at least that it forms an essential part of us that we cannot do without. We have made it ourselves, often with blood sweat and tears, often at great sacrifice, and only at the cost of more blood, sweat, tears, and sacrifice will we relinquish it. We try to become this self, but the effort never succeeds to our satisfaction, so we make modifications and additions and subtractions. But this thing we carry can never fulfill the role we try to give it–it can never be our identity, much less give us peace, and the reason is that God knows nothing about it. God knows only you, and he will not accept this counterfeit you have created. And the great tragedy is that although this shadow cannot be made into an immortal self, it is possible for you to lower yourself to its level. And many there are who, preferring their own creation, become shadows.
As a general rule, humanity is not very good at recognizing illusions. In fact the basic lesson of the Garden of Eden is that we are easily deceived. The false self is an act of perpetual self-deceit, constantly working to convince ourselves that we not only can but should be that which we are not. We can, but we should not, if we wish for everlasting life.