For many of us this has not been our full reality. There are still many areas in our lives in which we are not new creations. Areas in which we need to change. To claim your position in Christ you must follow the example of King David and affirm that position in Christ. Putting off the old and putting on the new is a progressive process.
Affirmations of faith are part of that process of change.
Lets assume that you want to change from being a person who grumbles and complains about your lot in life to a positive thankful person. There are five steps you must take to make an affirmation effective. Cancel the old messages you must you have been giving your subconscious mind through repentance. God forgive me for grumbling and complaining and focusing on what I don't have rather than what I have and give me a spirit of contentment. Replace the old messages with the new messages that reflect your true position in Christ.