The Essence of Man

What is Paul's or the Bible's view of the human being as to their essence? What lies at the foundation of our being? When Paul declares that we have been baptized into Christ and into His death; when stating that we were buried with Christ so that we may walk now in newness of life; when he says we have been united or planted together with Christ in the likeness of His death so that we may be in the likeness of His resurrection; when he says that our old man was crucified; that we have died to sin, that we are free from sin, that we are to reckon ourselves dead to sin and alive to God in Christ Jesus our Lord… We must ask the question who or what of ourselves is Paul addressing? Now this may sound like an unnecessary philosophical question but actually it is quite important, and I hope you see that the answer to this question will be a very practical thing for us to know and find out.