The "old Adam" is the religious fraud. He is more about what he can do. He is constantly looking for places where he can insert himself into the equation and climb up the rungs, either of carnal pleasure or of religious piety. He wants to talk about his "decision". He wants to peer into the mysteries of heaven with his charismatic craziness or overzealous doctrinal precision. Looking back into the fall of man in Genesis 3, we see that the old Adam is the man who disbelieves. He is not content to be a mere human who lives in dependency on God, with limitations and the presence of mystery and less-than-total-control of his life and world. He wants to transcend, to rise up into the clouds.
The "new Adam" is the man of faith. He comes back down to earth out of the clouds. He is content to have God be God, who holds his life and all the answers and all the mystery in His capable and good hands, choosing as He wills to reveal what He wills when He wills. He is content to look at creation with appreciation and love, taking upon himself what God would have him do as a steward of it.
The Gospel is meant to put to death the old Adam and raise up the new. It is not meant to help us get to the top of the ladder in an easier way, by making a decision for Jesus who did it all. It is not meant to give us our "best life now." It is meant to kill the self-governed, self-seeking, glory mongering, take-control-of-my-life religious fraud in all of us, and to raise up the man of faith... the man who is content to see how God has revealed Himself as a baby, born of a virgin, grown into a man, who lived, loved, and then died for our sins, and rose again as the first-fruits of this new creation of a kingdom of faith.
How much of today's "Christianity" supports the old Adam by catering to his view of life as a "ladder?" What things would you try to change, say in your local church, with the hope of helping bring things back to a clearer grasp of the Gospel and the Gospel-led life? Where would you start? I know it sounds all pious to say, "With myself." That is a given. But while you work on "getting there," which will never fully happen, the church continues in it's present direction unchanged. That may be fine. It may not be. But that kind of pious answer can just be a great Christian-sounding excuse to not get involved. So really, getting practical... what would you do and where would you start?