Above all God desires unity with us; the same unity that He shares in the Trinity.

When we sin, there is less unity.

When we don't do His will, less unity.

When we are vain, less unity.

When we doubt, less unity.

When we don't "give assent" to His revelation, less unity.

Our intellect has limits.  

When we let our pride tell us that our intellect has "it all figured out", less unity.

Our intellect in this sense becomes closed off within itself and this God can not be intimate with it, He is unable to "deal with" (engage, accompany) it as fully as He desires.  It's running on its own so to speak.