The Soul-Winner's Secret demonstrates a series of techniques and traits which ministers and missionaries alike must employ to convert wayward souls to the cause of Jesus Christ. Winning souls is not easy or for the fainthearted; often, those who have strayed from the embrace of the Lord are either ashamed or of poor moral character; consequently, they feel unable to reconcile with the Christian faith. Brengle demonstrates how winning souls to the cause is a matter of having the correct message in mind, possessing the means to perceive the character and desires of others, and preserving one's own health and the finances of one's church. Samuel Logan Brengle was an early commissioner of the Salvation Army; a position which led him to encounter many unfortunate people. The organization would help many thousands of unlucky individuals who had been variously struck by poverty or misfortune; setting these souls back on their feet remains the organization's mission to this day.

In this classic manual of faith, Reuben Archer Torrey examines the Holy Spirit, that readers may appreciate its divine nature. Describing the Holy Spirit with close quotations of scripture, Torrey immerses us with clarity supported by the Biblical New Testament. We learn how the Holy Spirit is distinct from both God and Jesus Christ, how it affects the material universe and every one of our lives, and how it was an important witness to the life and doctrines of Jesus. It is the Holy Spirit that acts to set believers on a path of ridding themselves of sin. We are all Sons of God; it is by guiding us towards that sensible eventuality that the Holy Spirit works its essential good within each of our souls. It not only fulfills a role as an educator of Christians needful of faith, but supervises the baptism and informs some of the greatest prophets, saints and apostles of spiritual wisdom.