Purity of Heart is a passionate call by the founder of the Salvation Army for readers to live a life closer to God and follow the essential message of the Holy Spirit.

Having witnessed much suffering in his vocation as head of a charity committed to assisting the misfortunate and destitute, William Booth was moved to write several books and essays upon principles of the Christian faith. This manual concerns the concept of purity, and how the attentive and devout person may attain a truly pure spirit and enjoy a good relationship with the divine.

Booth's gift as an author shine in this short yet deeply impacting work. He engages the reader as an equal, with a conversational style that does not condescend, belittle or awe. A reading of the text gives the image of a skilled preacher, assured of the value of his message yet understanding of his flock's anxieties and life concerns.

Keen to avoid high-minded or overly theoretical discussion, William Booth balances encouragement with practical steps to attaining a pure heart. Moderating one's temper and pride, and engaging one's God-given talents in both work and play are identified as the first steps to a purer heart and soul. Resisting the urge to take revenge or bear malice to others is another component to purity, that each believer benefit from the Lord's blessing.