Abstract: Numbers have consistently constituted an integral part of the structure of sacred literature in ancient Mesopotamia, and the major religions that emerged in this region and its surroundings are indebted to this ancient legacy. At the heart of Sassanid Babylonia, Manichaeism, drawing upon the core teachings of preceding religions, employed specific numbers to convey key religious concepts. This article seeks to analyze Middle Iranian manuscripts recovered from Turfan, Xinjiang, China, in order to identify the metaphors and similes used by Manichaeans to present Mani’s heptad writings. This study provides documented evidence of how Mani portrayed himself as a healer and physician, and how his works—referred to in authentic Manichaean texts as “the seven efficacious jewels”, “the seven healing tools”, “the seven precious rock crystals”, and even, in emulation of Zoroastrian teachings, “the seven fragrant fires” were regarded as remedies for the human soul. This study explores not only the central role of the seven books of Mani and the associated religious approaches in Middle Persian and Parthian texts, while also drawing on non-Iranian sources such as Coptic and Greek texts to interpret the findings, but through a textual approach tries to reexamine some earlier perspectives. Manichaean use of the number seven was not only deeply rooted in Mesopotamia and Iranian thought, but also enriched by the Gnostic-Christian heritage. Mani must be recognized as one of the greatest systematizer of the theology of numbers in the ancient world.