Spiritual or Mental?

Excerpt from The Messenger of the Cross by Watchman  Nee:

Page 80-81:  "Today's danger is that many people are seeking the knowledge of the Bible with their mind.  They understand a few mysteries, comprehend many spiritual principles, dig out some deeper meanings of God's word, and even appreciate to a certain degree the accomplished work of Christ.  Yet these are all in their mind.  These are not given them by the Holy Spirit and there is therefore no practical power involved.  With the result that the Bible is reduced to the level of a scientific treatise in which the reader and the writer have no personal contact whatsoever.  On the other hand, the word of God--though its contents had been spoken long ago and later recorded in what we have as the Bible--is nonetheless in the Holy Spirit even as God is in the Spirit.  If the reader receives God's word directly without leaning on the power of the Spirit, he will have no relationship with God.  This will reduce the value of God's word and make it as one of the dead books of the world."