You have to continually affirm what God’s Word says until it gets into your spirit and becomes a part of you. Nothing happens overnight. Your spirit man must dominate the natural man and bring it into submission with God’s Word, which is obedience. The body will obey words. The body has to be trained to act upon the Word of God. Your body will obey the commands of your mind. What you speak out of your mouth is because it is abundantly in your heart. What you say can cause sickness and disease or it can stop it. Jesus was given all power in heaven and on earth. Jesus delegated God’s authority back to man making him a joint-heir with Jesus to the kingdom of God. The law of Genesis says everything produces after its kind.
God has given every man the same measure of faith at conception so that they can be born again should they so choose. This spiritual seed of faith we all receive needs to be developed. The goal is to grow our faith into the God kind of faith, or as close as we can make it. How do we grow our faith? Scripture say faith comes by hearing and hearing by the Word of God. Basically, listen to the Word of God, but also read it and speak it. God’s words in your heart spoken out of your mouth release the God kind of faith. God’s Word plus faith is what works. It’s not the prayer in itself. The devil can say a prayer but it’ll never work because he doesn’t have the faith it takes to create spiritual power.
Sanctification is a lifelong process whereby you become more like Christ over time by agreeing to the process through your prayers, worship, meditation, service, giving and Bible study, etc. The active partner who will change you and do all the work is the Holy Spirit who will lead you to the fruits of the Spirit, namely love, joy, peace, patience, kindness, gentleness, goodness, faithfulness and self-control. When we stand before God at our death hopefully a lot of our remake will have been completed. In any event, God Himself will make the final changes in us to make us fit for heaven in a process we call glorification. Sin is not allowed in heaven and God will remake us so that we cannot sin. I used to worry about that but God has it covered so let’s relax. God has thought of everything so not to worry. God is for us all the way.