Our present is the result of our past. This is why we have virtually no power over the present; it is the logical outcome of our past.
The thoughts, feelings and desires we had in past incarnations triggered powers and forces of the same kind in the universe, and today it is they that determine our strengths and weaknesses and the events of our lives. This is why it is almost impossible to change the circumstances of this life, which are directly determined by past incarnations.
The only thing we can do is prepare the future. And this is what initiates teach in their schools: how to prepare the future.