I have been crucified with Christ; it is no longer I who live, but Christ lives in me; and the life which I now live in the flesh I live by faith in the Son of God, who loved me and gave Himself for me.
Who is Paul referring to that was crucified? He was of course referring to his spirit man, not his soul nor his body. The disciples in referring to themselves in the first person referred to their spirit man within, the real you. Most Christians are body or soul conscious because when talking about themselves that is what they are referring to.
You must become spirit conscious if you want to walk by faith in the body you live in, for faith comes from your heart not your head. You are a spirit, not a body nor a soul; you have a soul and you live in a body. Once born again we are to walk by faith not by sight. But if we associate ourselves as a body or a soul and we are not spirit conscious we will walk by sight and not by faith missing out on what God wants to do in and through us.
So go to the New Testament and start meditating on the scriptures that reveal the real you, the “new creation” you become once born again. These are the “in Christ” scriptures just like the one above. This will make you conscious of your spirit man, the new you. Develop the man on the inside, and it will help you learn how to walk by faith and not by sight.