Eye of Horus

The Eye of Horus (previously wadjet and the Eye of the Moon; and afterward as The Eye of Ra) is an ancient Egyptian symbol of protection and royal power from deities, in this case from Horus or Ra. The symbol is seen on images of his mother, Hathor, and other deities associated with her. In the Egyptian language the word for this symbol was "wadjet". It first was the eye of one of the earliest of Egyptian deities, Wadjet, who later became associated with Bast, Mut, and Hathor as well. Wadjet was a solar deity and this symbol began as her eye, seeing everything. In early artwork Hathor is depicted with this eye as hers also. [1]  
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Eye of Horus or Osiris One of the names by which the Egyptian symbol of the eye is known, especially its hieroglyphic representation, designated Utchat in Egyptian. There were, in fact, two eyes: one the symbol of Thoth (Tehuti), representing the full moon; the other, the utchat of Ra (or Osiris), representing the midday sun. When referred to as the eyes of Horus they were designated as the white and the black: the white eye standing for the sun, the black for the moon. Or again they were called the right and the left, referring respectively to the sun and the moon.
"The Sun was always called by the Egyptians 'the eye of Osiris,' and was himself the Logos, the first-begotten, or light made manifest to the world, 'which is the Mind and divine intellect of the Concealed' " (SD 2:25). This symbol connects Horus with the characteristic nature and functions of the manifest Logos which spiritually surveys all, guides all, and watches over all; and as the Logos contains in itself all that is, both of spirit and matter when they are manifested, the reason is seen for the more detailed ascription to sun or moon of this or that function or activity of the Logos.