In this article, the author demonstrates the spiral as being the basic symbol of the system of signs used in the Kongo religion, the Bukongo, to convey spiritual teachings as well as to help the initiates recall what they have been taught. This symbol is shown to be the summary of the teachings of the Bukongo; it explains the celestial origin and destiny of man, the divine completeness of being (the Verb) and universal salvation. The spiral simplified at the most results in the Kongo cosmogram; thus, this article shows that beyond its current cosmological interpretation, the Kongo cross is the synthesis of an African theology. The author also exposes the existence of the spiral in other African cultures in connection with the origin of mankind.