Who am I is a question that echo's throughout the ages into the present day. It is like trying to nail jello to a plank; it just makes a mess.
We try to think and speak in terms of absolutes. I am this. Then what about that? I am spirit. Then what about form? I am life. Then what about death?
Is it because we fear death that we need to know our life is spent in the proper way so that we will be judged accordingly. No one truly knows through personal experience unless we acknowledge those who speak of reincarnation.
We are as we act. Can we any less or any more?
All I know is that I am sometimes this and sometimes that and it is enough for me to try and live as fully as I can in the present moment without absolutes and leaving the judging to others.