The excellence of knowledge is that wisdom gives life to those who have it (see Ecclesiastes 7:12). Lets face it, there is no shortage of info out there. Simply click a button and voila, knowledge at our fingertips! And since knowledge is power, the more we have of it and can apply, the better off we are right? Not necessarily, for knowledge when misapplied is power misused!
Just as a buttering knife in the hands of a nutter becomes a destructive weapon, so does knowledge in the hands of a person devoid of wisdom. And since the bible tells us that Jesus became our wisdom (see 1 Corinthians 1:30), we can say that the application of knowledge without the help of God (wisdom) is foolishness (the opposite of wisdom) and leads to death (the opposite of life).
Therefore, it is possible to be extremely knowledgeable and still be extremely foolish; to know much scripture without it ever yielding fruit. This is why knowledge alone should not impress us much!