Paul defines the difference between walking in the Spirit and walking in the flesh (carnality) particularly in Romans 6. It is the method by which we deal with sin in our lives, whether relying on Jesus or on ourselves. In the flesh, we can never please God. You cannot ever accomplish even the most sincere efforts to rid yourself of sin. You can't please God by trying to be good because it is the Father's good pleasure to GIVE you the Kingdom. You're not trying to get into the Spirit. Paul says, "You are not in the flesh. You are in the Spirit." Present tense. You sink back into what is already there. If you present yourself as "under" you will always be "under". If you present yourself as "trying" to be something, you are saying that you are under it, trying to overcome it. The truth is that you have been given everything you need in Christ Jesus. When you believe and receive that revelation, the struggle falls off. The Gospel is simple. When people try to come up with new carnal ways of overcoming the carnal, we are complicating the simplicity of the Gospel. If you can enjoy God's love for you, even while you have a habit you don't like, that habit will fall off eventually because of the fullness and completeness you are experiencing while enjoying God's love for you. You are free in God despite you.