First spirit, then soul, then body. At the New Birth, our spirit was quickened from death to life. That was instantaneous. The second, and the hardest process, is the sanctification of our soul. The truth of the matter is, this process isn't hard at all. It's only because of the way we have always been trained to think - by our soul (the mind, the will, the emotions, the intellect) that causes this stage of growth to be so difficult. Enter the Holy Spirit, our personal Tutor - to expedite the process. How can we speed up this stage of our spiritual growth? By turning ourselves over to the Third Member of the Godhead. This is the ministry, the assignment, that He has been sent to perform in the earth in each and every one of us as believers.
Through the Baptism of the Holy Spirit with the evidence of praying in tongues, we are able to shut off our minds and our spirit does the praying (Romans 8:26). To the believer, our mind - our natural thinking - can be our own worst enemy. Because we have been trained to think a certain way by the world's system, we have to "un-learn" everything that we have learned previously through the tutelage of man. We cannot operate with the Mind of Christ otherwise. This Mind is part of the inheritance that we have been given freely as sons and daughters of the Most High. It is only by operating in the Mind of Christ that we are able to fully obey the instructions that are given to us during daily fellowship with the Holy Spirit. This is a requirement of every son and daughter - our "reasonable service" (Romans 12:1-2; Proverbs 8:34). Total life prosperity is the end result (Psalm 1:1-3; Joshua 1:8).
Satan has tried to counterfeit this operation of the Holy Spirit through various forms: Transcendental Meditation (TM), Zen Buddhism and other Eastern religious practices are just a few. Even the Church of Scientology uses the term "clear" to describe what its followers do in order to de-clutter their minds so that they are able to receive the brainwashing that this cult utilizes.
The reason why this process of renewing of the mind remains such a challenge to the believer is because that is the primary area that the enemy attacks. His assignment is always to entice you to make the wrong decision. This is done through emotions that are empowered by circumstances and the systems of thoughts that drive those emotions. The only way to to combat this assault is to employ 2 Corinthians 10:3-5. Nothing else. You don't reason with the devil. That is a fight you will never win. You use the Word of God ONLY -- and while you're at it, remind him of his rightful place -- under your feet. Then you tell him to SHUT UP, and COMMAND him to leave. He has to. You have that kind of authority through your new nature, the position of right standing that you have with the Father through the finished work of Jesus the Son on the cross. This is the position that your Comforter/Helper has come to help you to enforce.
The whole Truth is this: maintaining the position that you have attained through the shed Blood of Jesus on the cross is not hard at all. It's easy. Religion has lied to us long enough, and we don't have to listen anymore. This is an "open book" test. All you have to do is open The Book. The answers are all right there. If you don't know how to find them, ask the Holy Spirit. After all, He wrote it! (2 Timothy 4:16-17)