Knowing about God and knowing God are two very different things
Those of us who come from a tradition of doctrinal Christianity, for which we are grateful, can very easily turn doctrine into something that harms us. We can do this in two ways. Doctrine can stumble us if we confuse knowing about God for knowing God himself. Doctrine is meant to be a means to something else, not an end in itself. Knowing about God is infinitely easier than knowing God. The former is merely an intellectual activity, the latter a serious and costly engagement which transforms mind - yes - but heart and life also.
Primary doctrine, secondary doctrine
Doctrine can stumble us in another more subtle way - it can stunt growth. If for example, we pursue a doctrinal understanding of where we stand on every single issue we can think of, including what Paul calls those "disputable matters" in Romans 14:1, how then can we grow the rest of our lives? If we know everything, what is there left to know? And worse, what if we settle too early on certain positions only later in life to be totally resistant to change, resistant to where God might be leading us then? Either we will never change, never grow, or we'll be stumbled by the change because we thought we knew for sure, and now we're doubting (not central truth, but disputable matters).
When I was a younger man, I worked out every doctrine one could. I knew where I stood on spiritual gifts, translations, the gifts of the Spirit, eschatology, you name it, I had nailed it. This is because I went to a church that emphasized (no, over-emphasized) doctrine, at the expense of love and grace.
The last 30 years have been spent, little by little, unknowing what I "knew" as God has challenged almost every single of the secondary doctrines on which I was so sure!
Don't get me wrong, there can be no change on the primary doctrines, no change on atonement, no change on the trinity, no change on justification by faith, on heaven and hell, and so on. But there are a lot more secondary doctrines than primary ones, and year by year I find myself discovering from Scripture that what I nailed as a zealous 20-something is not so nailed anymore. I have so many "not sure about that one's" on my creaking shelves these days.
Desperate need for doctrine today
Don't get me wrong, there is a desperate need for doctrine in the church today. We live (at least in the UK) in an age of tremendous theological shift - large areas of what would once have been called evangelicalism are succumbing to the liberalism-in-sheep's-clothing of men like Steve Chalke and his teacher Tom Wright. We live in perilous days. But the answer to doctrinal indifference is not indoctrination. It is a gracious humble teaching of central doctrines, prayerfully seeking to know the God they attempt to describe, and an even humbler teaching of secondary "disputable matters" in a way that builds up, not puffs up.