Mathew 6:
"The Light of the body is the eye: if therefore thine eye be single, thy whole body shall be full of light."
Upanishads, Seventh Khanda:
" 6. He is lord of the worlds beneath that (the self in the eye), and of all the wishes of men. Therefore all who sing to the vînâ (lyre), sing him, and from him also they obtain wealth."
The 6th Chakra: Anja
"The sixth chakra is the source of internal visions, telepathy, and intuition. Located at the level of the forehead, this chakra, known also as the third eye, or Anja, is the energy center from which we draw our dreams, memories, and visions. From the sixth chakra, we gain the ability to discern the truth and see the past, present, and future in detail. The blessings that come into our lives are often the result of the images we are able to perceive via the sixth chakra. In Sanskrit, Anja means both "to perceive" and "to command," because when this chakra is strong, visualization is the first step in manifesting your desires.
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On Plato:
"Among the wisest men of Greece arose the saying that Plato had three eyes: one with which he looked at human things, another at natural things, and another at divine things. The last was in his forehead, while the others were under his forehead."
"If one is whole, one will be filled with light, but if one is divided, one will be filled with darkness." (Gospel of Thomas)
"Do not cease seeking day or night until you find the mysteries of the Kingdom of Light, which will purify you, make you into pure Light and lead you into the Kingdom of the Light." (Yeshua, Book of Pistis Sophia)
"If therefore be thine eye single thy whole body full of light shall be." (Yeshua, Matthew 6:22)
"Thus as a result of recollecting all these things the impulses of the mind are extended from the sphere of material things towards those impulses which are without limit, that is to say, wonder at the New World, and the faculty of vision which belongs to contemplation of the Holy Trinity. For when the vision of the mind is mingled with the Light of the glorious Trinity, all its impulses become infinite. For none of the Visionaries or 'Gnostics' is able to distinguish the identity of the mind as a result of the vision of that glorious Light that is seen of the Holy Trinity, for all the innermost chambers of the heart are filled by that blessed Light, and there are no shapes or forms or anything material, or number or colour; rather that Light who cannot be separated out into shapes and forms is single owing to the simpleness of the faculty of sight."
(Joseph the Visionary, in, The Syriac Fathers on Prayer and the Spiritual Life, translated from the Aramaic by Sebastian Brock)