When you let God take a hold of your life, you begin to become who you are while also staying who you are. Meaning over time you become the sanctified person God has already declared you to be, and at the same time you retain your personality and will.
When God called Abraham, He renamed him from Abram to Abraham, which means “father of a multitude,” yet at the time Abraham had no children at all. As God made him over time what he was, Abraham still got to make his own choices about how he participated in this plan. They were not always good choices, but God lets us keep trying. (See also Why Would God Call Me That?)
When God called Paul the apostle, He had major plans for him as well. While other Christians still feared Paul for his zealous persecution of the church, God had already called him to stand before kings (or rulers) to proclaim the Gospel. Paul eventually did stand before kings, and all the while on his way he retained his zealous personality, just pointed in a different direction. (See also True Potential)
God knows who and what you are, and He has just the right plan. You were made for the plan and the plan was made for you. God does not disregard who we are or take away the volition and talents He gave us. We are allowed to participate in God’s plan. Do we allow God to use us as we were meant?