"Our wisdom, in so far as it ought to be deemed true and solid Wisdom, consists almost entirely of two parts: the knowledge of God and of ourselves. .... man never attains to a true self-knowledge until he has previously contemplated the face of God, and come down after such contemplation to look into himself."That is the starting point for all knowledge and understanding - God himself. Without an infinite all-knowing all-powerful all-Sovereign being there is no true knowing for nothing is fixed and therefore nothing can be truly known. By definition God must possess these expansive qualities or there is something greater than he in the universe and that greater thing would be greater than God and thus truly God. But God must be God and therefore is the source of all truth and only from Him can we know truth definitively.Calvin, Institutes of the Christian Religion, Book 1, Chapter 1.
As one great philosopher said (much more simply):
"The fear of the LORD is the beginning of wisdom,Want Wisdom? Fear God.
and the knowledge of the Holy One is insight."Solomon,Proverbs 9:10, ~950 B.C
(~600 years before Plato and all those guys that followed !)