In some gnostic systems the Supreme Being is known as the Monad, the One, the Absolute, Aiōn Teleos (the Perfect Aeon, αἰών τέλεος), Bythos (Depth or Profundity, Βυθός), Proarchē (Before the Beginning, προαρχή), Hē Archē (The Beginning, ἡ ἀρχή), the Ineffable Parent, and/or the primal Father.
Prominent Christian gnostics like Valentinus taught that the Monad is the high source of the Pleroma, the region of light constituting "the fullness of the Godhead." Through a process of emanation, various divine entities and realms emerge from the One. Arranged hierarchically, they become progressively degraded due to their remoteness from the Father. The various emanations of the One, totaling thirty in number (or 365, according to Basilides), are called Aeons. Among them exist Christ (who resides close to the Father) and the lowest emanation, Sophia (wisdom), whose fall results in the creation of the material world.
According to Theodoret's book on heresies (Haereticarum Fabularum Compendium i.18), the Arab Christian Monoimus (c. 150-210) used the term Monad to mean the highest god that created lesser gods, or elements (similar to Aeons). In some versions of Christian gnosticism, especially those deriving from Valentinius, a lesser deity known as the Demiurge had a role in the creation of the material world separate from the Monad. In these forms of gnosticism, the God of the Old Testament, Yahweh, is often considered to have been the Demiurge, not the Monad, or sometimes different passages are interpreted as referring to each.
The Apocryphon of John: The Secret Book of John written circa 180 ce gives the following description: “The Monad is a monarchy with nothing above it. It is he who exists as God and Father of everything, the invisible One who is above everything, who exists as incorruption, which is in the pure light into which no eye can look. “He is the invisible Spirit, of whom it is not right to think of him as a god, or something similar. For he is more than a god, since there is nothing above him, for no one lords it over him. For he does not exist in something inferior to him, since everything exists in him. For it is he who establishes himself. He is eternal, since he does not need anything. For he is total perfection."  A being can have a relationship with a God but not the Monad as that would be a contradiction. The Apocryphon of John was banned by the Christian Church and rediscovered among other gnostic texts in a large jar at Nag Hammadi, Egypt in 1945.
According to Hippolytus, this view was inspired by the Pythagoreans, for whom the first existing thing was the Monad, which begat the dyad, which begat the numbers, which begat the point, begetting lines, and so on. Pythagorean and Platonic philosophers like Plotinus and Porphyry condemned the "gnosis" that would later characterize Gnostic systems for their treatment of the Monad or One (see Neoplatonism and Gnosticism).
For a long time, legend persisted that a young man by the name of Epiphanes, who died at the age of 17, was the leader of Monadic Gnosticism. However, scholars think the legend may have come from misunderstanding of the Greek word epiphanēs which may have been mistaken as a personal name if in text, when in fact the Greek means distinguished, as in a distinguished teacher.
- Francis E. Peters Greek Philosophical Terms: A Historical Lexicon 1970 p. 42.
- Louis P. Pojman, "Valentinus," in The Cambridge Dictionary of Philosophy, 3rd ed., ed. Robert Audi.
- Louis P. Pojman, "gnosticism," in The Cambridge Dictionary of Philosophy, 3rd ed., ed. Robert Audi.
- "Principles of a New Religion" by David Griffiths pp 60-4 https://www.amazon.com/dp/1095854232
- Diogenes Laërtius, Lives and Opinions of Eminent Philosophers.
- Mead, G.R.S. 1900. "Epiphanes, Fragments of a Faith Forgotten, pp. 232-235, available online by The Gnostic Society Library.