Isaiah 40:28 Hast thou not known? hast thou not heard, That the everlasting God, the LORD, The Creator of the ends of the earth, Fainteth not, neither is weary? There is no searching of his understanding.
God is everlasting. That is impossible for us to understand. When did He begin, never. When will He end, never. He is the creator so He stands above and beyond all. We are simply creation. We have a hard time with that. We make things so it is hard to consider that God would make us. We consider ourselves to be very large, capable, intelligent, etc. We must sleep yet He never sleeps or even gets tired.
To sum it all up He is beyond our understanding. We will never fully comprehend who He is. He is our maker. He is above us. We will love Him and serve Him and never fully understand someone so great and so good.