John Calvin begins his Institutes by arguing that one must know himself in order to know God, and one must know God in order to know himself. These two realities obviously have to be interrelated.
If one doesn't know himself, he won't be driven to seek after God. Without self-examination, we think we're pretty decent people, and we think that our talents and abilities are our own, derived from no one else. But upon examining ourselves, we recognize that our talents and abilities are hardly our own, but our derivative of another source. And we also begin to recognize how broken we are, how depraved, corrupt, and morally bankrupt. Then we begin to seek God. "We cannot seriously aspire to him before we begin to become displeased with ourselves."
But the reverse also holds true. We don't truly know ourselves until we know God. Apart from God, we are satisfied with our own righteousness, for the standard we have to compare it to is the impure standard of the world around us. "Just so, an eye to which nothing is shown but black objects judges something dirty white or even rather darkly mottled to be whiteness itself."
But once we behold God in his majesty and holiness, we suddenly become quite ashamed; worse, undone, as Isaiah was (Isa 6), as well as Peter (Lk 5), Job (Job 40:1-5; 42:1-6), and John (Rev 1:17).