The Gnostic's conception of a creator god, known as the Demiurge, may have derived from Demiurgos, a figure from Plato's Timaeus and Republic. Out of chaos, the Gnostic Demiurge created the imperfect copies of the divine model that either purposefully or unconsciously trap divinity in matter. This seems to suggest the pre-existence of particles of matter out of which the universe could be created. Further, they distinguish this evil materialistic world from the Pleroma, the world of wisdom, light, truth, and reality. The human body imprisons the sparks of the Divine, and it is only through the ascent from the physical world back to the Pleroma that the soul finds salvation. A Gnostic savior or revealer is one who comes to awaken those asleep or “slumbering” in darkness.

Plato asserted that the cosmos emanated from the transcendent unknowable One and was created by the Demiurgos out of passive matter in chaos. The Demiurgos, according to Plato (writing in the Socratic dialogue Timaeus), is a benevolent entity, a “craftsman,” who cobbled together the world out of pre-existing matter that resisted the effort — and thus the world remains imperfect. Plato expressed through his philosophical writing in Phaedo the idea that physical bodies are ephemeral and are only imperfect copies of the eternal forms. Also in Phaedo, he argued the idea of immortality of the soul. These two concepts resonate in Gnostic thinking.

Gnostic beliefs also reflect Plato's ideas about metaphysics — in particular, his dualistic concept of the world having two aspects, intelligible and perceptual. The intelligible aspect consisted of the world of forms (or “ideas”) and the perceptual aspect consisted of the world of replicas of those forms (carbon copies of the original). The true forms/ideas (not copies) can only be comprehended by the intellect, and such comprehension of reality is the goal of all knowledge.

Plato espoused that the essence of something (for example, a Judean date palm) was its form. The plant could grow through all the stages from a seed to a young palm and then a frond-covered mature tree laden with succulent dates, but through each stage or change in substance, the tree's essence (its form) is always present and is only being embodied by substance. This resonates with the Gnostic idea of the divine spark, unchanging, though embodied in matter. The object of knowledge is to break through to the underlying reality behind false forms of this world, and to understand that reality — that world of being that always is and never changes — is comprehended by the mind, not the senses or the imagination.

Plato's dualism expresses the idea that the human body is different than the soul. The body is simply a container or temporary housing for the soul. Plato suggested that the soul came from the world of ideas, a spiritual realm, before it entered the body. Once in the body, it became the overseer of the human. A saying of Plato reflects this idea of dualism perfectly: “Man is the soul which utilizes the body.” In Timaeus, Plato offers further clarification.

Christian theology was anchored in monotheism, or the belief in one god, a concept that early Christians shared with Judaism. Monotheism was also the basis of Islam. In opposition to the concept of the Demiurge, most early Christian fathers rejected the idea that any being other than God created the cosmos. They believed that a benevolent God created the world out of nothingness, unlike Plato's Demiurgos who created the world out of matter that already existed in the chaos.