Doddridge discusses the conviction of sin, conversion, doubt and assurance, the sacraments, the emotions, temptation, joy, sanctification, death, mercy, the hiddenness of God, as well as many other topics.

This book made a great impact on the famous English abolitionist, William Wilberforce, John Newton, the author of the hymn "Amazing Grace," and Jonathan Edwards, America's renowned preacher and theologian.