Love takes up where knowledge leaves off. 

- St. Thomas Aquinas

A priest once told me that one of the most difficult journeys for people to make in the spiritual life is the journey from the head to the heart. I remember when I first converted to the Catholic Church. I was so hungry for knowledge of my new faith. I repeated another year of RCIA because I wanted to be sure I hadn't missed anything the first time. And then I took a correspondence course in Catholicism to learn even more. It was like I was starving. I couldn't get enough knowledge.
That hunger was important because it helped me to learn and know my faith. And it still is important. We can never know it all. And how can we defend our faith and explain our beliefs if we do not understand them?

But there is a difference between knowing about God and knowing God. We can know someone's birthday, for example, but do we know their heart's desire?
One can get stuck in the head knowledge and fail to make that connection to the heart. For some of us it really is a long and difficult journey. Especially for people like me who tend to fear intimacy. However, these days I really do yearn more for the intimate relationship with God, the heart knowledge.
I yearn to know God's heart.