The book is Kaplan's most notable work and has influenced a number of American Jewish thinkers.

Kaplan's work centers around the concept that Judaism ought not to be defined as the religion of the Jews, but the sum of Jewish religion, culture, language, literature and social organization.

In 1934, Kaplan published Judaism as a Civilization, a seminal work that eventually provided the theological foundation for the new Reconstructionist movement.

Kaplan was deeply influenced by the new field of sociology and its definition of "civilization" as characterized not only by beliefs and rituals, but also by art, culture, ethics, history, language, literature, social organization, symbols and local customs.

Kaplan felt that Jewish group survival in the United States depended on Jews reconstructing their lives on the cultural foundation of a historical peoplehood.