The purpose of Step by Step is to systematically examine what the Bible says about knowing the will of God. Petty looks at the lives of godly saints of the past have identified and how they have tested a foundation of powerful theological truths that can guide our way.
The Biblical doctrines of providence (something that he calls the guard rails of life) revelation, inspiration and illumination carry within them the answers which our theologically unaware generation needs. The saints of old asked the same questions, and all the did was go to scripture and found their answers - for the primary focus of this book is to see what the Bible says about guidance.