1 John 1:5
This is the message which we have heard from Him and declare to you that God is light and in Him is no darkness at all.

Only God is holy (to be morally clean without impurity). In other words, God cannot be one way one moment and a different way the next or He would be inconsistent, unreliable, untrustworthy and changeable. The words ‘light’, ‘purity’, and ‘holy’ all express the same thing about God; that His character is constituted of a singular motive, which is agape love. We tend to take for granted that God is immortal, indestructible, and omnipotent. We usually do-not question it. Have you ever wondered why God is immortal? Jesus shed some light on this in Matthew 12:25 “…every Kingdom divided against itself is brought to desolation: and every city or house divided against itself shall not stand”. Hence, if a kingdom is divided ‘against itself’, it will be brought to desolation – it will come to an end. We can conclude that God’s kingdom will never come to an end. This is an extremely important concept, “God is light and in Him is no darkness at all”. He is not divided between light and darkness. He never operates by a contradictory duality. He is light only, at all times and in all circumstances. Taken from GOT pp 8, 9