The old me rationalizes himself out of his troubles. He hears the Law and sees his salvation. He tames it first, to make it doable (at least for him, if not for those of weaker stuff). He redefines obedience and perfection in his own image - what is reasonable for him. Then he uses it to medicate his own guilt, salve his own conscience. He can do the Law. Just follow the program. Self-will, self-discipline, self-control, self-improvement - all will lead him ultimately to self-righteousness - and he will be ok with God and his fellow man. His troubles will be over.
On the other hand, the unconditional Gospel confronts the old me and causes him grief. He cannot believe that his valiant efforts are not needed, his sacrifices useless, his righteousness as filthy rags, his cooperation a sham, his faith a gift. Everything is already finished, done, accomplished. Someone else came and did his salvation business for him. This wrecks his self-esteem, turns him into nothing, defeats his purpose in life, kills his ambitions, crushes his ego, makes all things meaningless. What is the point of living now? There is nothing left to do, to think, to feel. He senses himself dying, and fights for life, as he understands life to be - the only life he knows. He sees only one option. He must fight against this Gospel. This Gospel must be silenced, compromised, watered down or ignored.
In his struggle to survive, the old me grabs for the most powerful weapon he has. He grabs the Law of God. He uses the Law as a weapon against the Gospel. He elevates it above the Gospel. He has to. The Gospel is killing him. The Law is his only defense. If it fails him, he will surely die. And that is exactly what happens. It is not a quick and painless death. It is a slow death that lasts a lifetime. The old me was as good as dead from the moment the Gospel told him so. But he fights on, oblivious, unconvinced and unconverted. He will never admit defeat. That is why he continues to vex me, and why he must eventually be put to physical death. In my physical death, the final victory of the new over the old will be complete. The old man will be gone, annihilated, never to be seen, heard or felt again. The new me, the true recreated one, will live on.
But this new man, the “me” who is born from above, is a present reality from the moment the old man is crucified with Christ. Without the new me, there would be no hope for me at all. The new me is the real deal, my true identity, a new creation of God. This me does not need self- esteem, because this me has the esteem of God. This me does not wonder about the will of God - my will and God’s are one, in Jesus. This new me thinks, acts and loves in harmony with the God who (re)created him and gave him life. He is a perfect re-creation of what God intended, because he is in Jesus. The new me is patient, kind, does not envy, does not parade itself, is not puffed up, does not behave rudely, does not seek its own, is not provoked, thinks no evil, does not rejoice in iniquity, rejoices in the truth, bears all things, believes all things, hopes all things, endures all things. The new me never fails.
This new me is not a puppet on a string any more than Jesus was a puppet of the Father. This me is a unique person of God’s own design - incomprehensibly one with God in Jesus, and yet still a separate person who loves and is loved. He is not a god, but he is in the image of God - just as his first parents were made in the image of God.
Like the first Adam, this new me has no sin. But this new me is superior to the first created Adam in a most important way. This new me, because he is in Jesus (the Last Adam), will not ever sin. This new me has the mind of Christ, and Christ has the will of the Father. So the Father’s will, through Jesus, is now my will. And this will, and the faith to believe it, is actually mine. It is gifted to me for no reason other than God wants to gift it. God loves me in spite of my old me, which is hopelessly lost and beyond repair.
So where exactly is this new me? I don’t often sense him or feel him. I would have to say that I don’t even know him. I can’t even imagine him. He would have to be so vastly different from the old me that I’m not sure I would recognize him if he showed up. If he did show up, I fear I would not even like him. Does he stay completely hidden within me? Does he ever reveal himself to me or others? Am I to think of myself as two people - the good me and the bad me? Or am I to think of myself as one person in two parts - the greater part evil, and some tiny (hopefully growing) part that me is pure and good? If there is truly an old me and a new me, who on earth am I?
This doctrine is ridiculous!
Ah, there it is - the logical mind of the old me at work, fighting for life. The old me is always recognizable. He is the one who will question the existence of the new me, for the new is the death of the old. The new me is recognizable only by faith. And here is the secret to recognizing the new me. Just as I cannot see the Father, except by looking at the Son, so I cannot see the new me, except by looking at the Son. For the new me and Jesus are one. I cannot dig down deep into myself to find the new me. It is pointless to look for the new me in my own thoughts, feelings, words or works - for all those can so easily be counterfeit - the old me, dressed up in self-righteousness, fighting for survival.
The only way to see the new me is in Jesus, and him I can see only through the eyes of faith. This faith is given and nourished by the Holy Spirit through the message of grace (the Gospel). Thus the grace message becomes a mirror that reflects the new me. Just as the Law is a mirror that shows me the utter sinfulness of the old me (even when I am being good), so the Gospel is a mirror that shows me the glorious righteousness of the new me (even when I am being bad). It does this by showing me Jesus (Christ in me). The Gospel shows me the Jesus who was born for me, lived for me, was crucified for me, rose again for me and then gave me the faith to believe on Him. Through these divine acts in history past, and by the power of the Holy Spirit in history present, Jesus created the new me to live forever in history future. I can gaze upon the new me any time I want, simply by holding up the Gospel mirror. There is no evidence of outward works or inner thoughts that could confirm the existence of the new me more powerfully than the Gospel proclamation, for it is the promise of God himself.
This, briefly, is my interpretation of Luther's doctrine of simul iustus et pecator - we are simultaneously saint and sinner. Lutheran theologians sometimes affectionately refer to this as - The Simul.