The Secret of the Ages shows the power of the subconscious mind, asserting deep revelation regarding the power of thoughts, the mind, and universal supply. It addresses the spiritual, mental and financial areas of life, pointing the importance of the right mental attitude in present and future success. Given that Collier trained to be a priest, the work contains a number of Biblical principles and quotes through which he tries to convey truths that have been substantiated globally.

Robert Collier (1885-1950) was an American author of self- improvement and New Thought metaphysical books in the 20th century. He was involved in writing, editing, and research for most of his life and his best known book is The Secret of the Ages. Collier wrote about the practical psychology of abundance, desire, faith, visualization, confident action, and personal development.