"Now we have received, not the spirit of the world, but the Spirit which is of God; that we might know the things that are freely given to us of God"
It is possible to grow up in a church, learn the catechism and have everything done to us that they do to us, within reason. But after we have done all that, we may not know God at all, because God isn't known by those external things. We are blind and can't see, because the things of God no man knows but by the Spirit of God.
We imagine that we can handle it by the flesh, and we do handle it by the flesh - the Lord lets us do it! We can hold the creed and not know God in His person at all. The fearful consequence is that many people know about God but don't know God Himself. There is a vast difference between knowing about God and knowing God - a vast difference!
So it is that the human being can know about God, can know about Christ's dying for him, can even write songs and books, can be the head of religious organizations and hold important church offices - and still never have come to the vital, personal knowledge of God at all. Only by the Holy Spirit can he know God.
Lord, it is humbling to consider the possibility that I could know all about You, and yet not know You personally. Impart Your Spirit, Lord, that I may truly know you. Amen
~A. W. Tozer