In the end it all boils down to faith. We each individually choose whether we will believe in God's word. We make this choice in our minds and spirit. If we choose to believe and read God's word......he will teach us and reveal much more than printed word to our spirits. There are many more messages in scripture that are revealed than could literally be counted as teachings.
These are God's truths and are hidden from the non-believers, else Satan could simply read God's word and know what believers know.
Those that won't put their faith in God are blinded from God's wisdom and allowed to trust in their own intelligence which God describes as a fool. They will reject God's existance as to justify their failure to put their faith in him.