God enlists our efforts in his work of changing us
Though we do have a role to play, that role is carried out only because of the prior working of God, and in dependence upon that fact. As Paul writes, “work out your own salvation with fear and trembling, for it is God who works in you, both to will and to work for his good pleasure.” (Philippians 2:12–13). We are called to work, but we are to work out our salvation, not for our salvation.
We have things to do, but God is in charge and is credited with producing the change in our lives. Aware that God is the author of our transformation, we are set free to put forth the most strenuous effort imaginable. We do not have to be paralysed by the fear of failure, nor do we need to throw in the towel when we are discouraged by the lack of progress. We are set free to skilfully apply the means of grace as we depend upon God to deeply change our hearts. (These means of grace will be spelt out in Units 2, 3, and 5.)