Without knowledge of God there is no knowledge of self
From Institutes, book one, chapter one, p. 37 (paragraphs added):
"Again, it is certain that man never achieves a clear knowledge of himself unless he has first looked upon God's face, and then descends from contemplating Him to scrutinize himself.
For we always seem to ourselves righteous and upright and wise and holy--this pride is innate in all of us--unless by clear proofs we stand convinced of our own unrighteousness, foulness, folly, and impurity.
Moreover, we are not thus convinced of we look merely to ourselves and not also to the Lord, who is the sole standard by which this judgment must be measured."
* The title of this post is Calvin's title to the quote above.