“These considerations lead us to an interesting topic, the Eye of Mind or the Eye of Horus ... and conveying the idea of the 'All seeing Eye.' The end set before the Egyptian neophyte was illumination, that is to be 'brought to light'. The Religion of Egypt was the Religion of the Light.” - Thomas Milton Stewart
In Ancient Egypt, Osiris was the SO BELOW God who represented the AS ABOVE planet of light, truth and life, Jupiter. Horus was the SO BELOW son of Osiris, and heir to the throne of the world. But unfortunately for Horus, he had many adversaries on the SO BELOW who happened to be members of his own family and that had wished to rule the world and take the throne from Osiris, AKA Jupiter. One of these deities on the SO BELOW, was a God named Set. He was the God who represented the dark ringed planet on the AS ABOVE, that we know of today as Saturn.
In one myth, when Set and Horus were fighting for the throne after Osiris's death, Set gouged out Horus' left eye. The eye was restored by either Hathor or Thoth. When Horus' recovered his eye, he offered it to his father, Osiris, in hopes of restoring his life. Hence, the eye of Horus was often used to symbolize sacrifice, healing, restoration, and protection.
From the Pyramid Texts (§ 1806) - "O Osiris the King, the gods have knit together your face for you and Horus has given you his Eye, that you may see with it." Also in the passage of (§ 1806) - the Ancient Egyptians had celebrated special events in festival form where they ran 3, 6 and 10 day events known as the festivals of Red Linen. This 10 day Festival is described in (§ 1067), and celebrated the periodic return of the Eye of Jupiter in coordination with earth's rotational status.
Jupiter as Lord of the world and the God by Law, is verified in an official treaty written in stone between Ramses II and Hattusili III of Hatti; the Hittite chief, where they refer to Jupiter as “the lord of the heaven.” This is where the phrase AS ABOVE, SO BELOW is derived, and how some governments rule over their people. The reason the Egyptians had represented Osiris and Horus with the All Seeing Eye, is because their planet Jupiter also has a giant All Seeing Eye. The mythologies of both the ancient Egyptians and Greeks throughout history tell of these spiritual and heavenly battles of the AS ABOVE, SO BELOW that govern the souls on earth.
Proclus gives us the following as one of the verses of Orpheus: “Jupiter is the king, Jupiter himself is the original source of all things; there is one power, one god, and one great ruler over all. But we have seen that Jupiter and all the other Gods were but names for the Sun; therefore it follows that the Sun, either as emblem or as God himself, was the object of universal adoration.”
"The physical universe is therefore the body of Jupiter, Jehovah, Osiris, or Shiva." — Manly P. Hall; Lectures on Ancient Philosophy
Albert Pike (1809-1891), Sovereign Grand Commander of the Ancient and Accepted Scottish Rite of Freemasonry says in the book Morals and Dogma; " His power was symbolized by an Eye over a Sceptre. The Sun was termed by the Greeks the Eye of Jupiter, and the Eye of the World; and his is the All-Seeing Eye in our Lodges. The oracle of Claros styled him King of the Stars and of the Eternal Fire, that engenders the year and the seasons, dispenses rain and winds, and brings about daybreak and night. And Osiris was invoked as the God that resides in the Sun and is enveloped by his rays, the invisible and eternal force that modifies the sublunary world by means of the Sun”.–(Albert Pike, Morals and Dogma, p. 477)
33rd Degree Freemason, Manly P. Hall in his book "Lectures on Ancient Philosophy," had written; "In man Jupiter has his abiding place in the human heart, while Neptune dwells in the brain, and Pluto in the generative system."
According to Albert G. Mackey; “On the same principle, the Egyptians represented Osiris their chief deity, by the symbol of an open eye, and placed this hieroglyphic of him in all temples. His symbolic name, on the monuments, was represented by the eye accompanying a throne… which may as correctly be supposed to be a representation of a square. The All seeing Eye may then be considered as a symbol of God manifested in his omnipresence.”
(Let him never forget that the Master is near. Day and night let him feel the presence of the Supreme or Overshadowing One. The All-Seeing Eye is upon him. Day and night this great Orb measures his depths, seeing into his innermost soul of souls, judging his life, reading his thoughts, measuring his aspirations, and rewarding his sincerity. To this All-Seeing One he is accountable; to none other must he account. This Spirit passes with him out of the Lodge and measures the Mason in the world.” (Manly P. Hall, The Lost Keys of Freemasonry, p. 62, edition 2006, original edition 1923). Emphasis added
“Symbolism is the language of the Mysteries ... By symbols men have ever sought to communicate to each other those thoughts which transcend the limitations of language. Rejecting man-conceived dialects as inadequate and unworthy to perpetuate divine ideas, the Mysteries thus chose symbolism as a far more ingenious and ideal method of preserving their transcendental knowledge. In a single figure a symbol may both reveal and conceal, for to the wise the subject of the symbol is obvious, while to the ignorant the figure remains inscrutable. Hence, he who seeks to unveil the secret doctrine of antiquity must search for that doctrine not upon the open pages of books which might fall into the hands of the unworthy but in the place where it was originally concealed.” — Manly P. Hall, The Secret Teachings of All Ages, p. 20