Being fully human does not mean realizing our greatest human potential -- the product of self-discovery and self-actualization. Being fully human means being and experiencing our God-intended humanity as fully and as freely as possible, albeit in the midst of the intensive and extensive fallenness brought on by sin.
To be fully human, we must recognize that we are no more and no less than human. It calls for more than this, but it doesn't call for less. Another way to say it is to say that we are not God and we are not animals. Distinctions should and must be made. The contention is that it is good for animals to be animals, it is good for God to be God, and it is good for human beings to be human beings -- and it's critically important and of inestimable value not to be confused about these things.
Yet, if we stopped here, we would not have gone far enough. For, realizing what we're not may be of some value in coming to terms with what we are, but it is not sufficient to tell us what we're meant to be. It's the difference between being human and being fully human. We may be able to be human through the realization of distinctions alone (though not likely), but by this alone, we would not become fully human.
Ironically, one of the reasons this is so is because we are merely human. Though we possess many amazing capabilities, as human beings, we are utterly incapable of ascertaining ultimate realities by human means. This is because we are not ultimate -- only God is. As the ultimate reality and absolute uncaused cause of all that is, God establishes and defines ultimate reality. As such, He is the ultimate explainer and interpreter of reality; so apart from God's disclosure, we could never come to know the meaning of our own existence and the significance of our lives. Consequently, we could never be fully human, for being fully human means being and experiencing our God-intended humanity. At best, we could only be merely human.
Yet, knowledge (or a lack thereof) is only part of the problem, for even should we come to know the meaning of our God-intended humanity, we lack the inclination to seek it and the power to experience it in it's fullness. The reason this is true is because sin has adversely impacted every aspect of our being and blinded us to the depth of its effects. No part of us is untouched by sin. Everything -- our body, mind, emotions, will, inclinations, dispositions, motivations, values, identity, sense of self, view of others, view of things -- everything has been tainted and skewed by sin. In fact, sin has so thouroughly affected every aspect of us that we don't even recognize it! And compounding the problem is the fact that we're not alone in this state: everyone else we encounter is likewise affected by sin. We are all sinnners, lacking sense. And adding to the problem still, we live in a fallen world. Creation itself has been cursed by sin and struggles under its dominion. The world and everything in it has come to know sin, and we are undone!
