The reason God is omniscient, that is, perceives, sees and knows everything is because He is Wisdom itself and Light itself, and Wisdom itself perceives everything and Light itself sees everything. It was shown above that God is Wisdom itself. He is Light itself because He is the sun of the heaven of angels, which sheds light on the understanding of every angel and every person. For as the eye sees by the light of the natural sun, so the understanding sees by the light of the spiritual sun. It not only sees by that light, but is also filled with intelligence the more it loves to receive that light, since this light is in its essence wisdom. Thus we read in the Psalms of David that God dwells in inaccessible light [Ps. 104:2; cf. 1 Tim. 6:16]; and in Revelation that in the New Jerusalem they have no need of a lamp, because the Lord God sheds light on them [21:23]; and in John that the Word, which was with God, and was God, is the light, which enlightens every man that comes into the world [John 1:1, 9]. By the Word is meant the Divine Wisdom. This is why the angels enjoy a brighter light, the greater their wisdom; and why in the Word, every time light is mentioned, wisdom is meant.