Here are a few books which have been of value to me in my journey.

• The Holy Spirit or Power from on High – Vol 2 by A.B. Simpson  This 2 volume set by A.B. Simpson is a high level overview of the actions of Holy Spirit as seen throughout the Bible. Volume 2 deals with the work of the Holy Spirit in the New Testament. Simpson did not write as an academic exercise. Simpson wrote that men and women born of God could see the work the Spirit in their lives in a similar manner as seen in the early church, that they may walk with power from on high. 
• The Cloud of Unknowing  – 14th century English mystic. Introduction into the contemplative art.
• The Book of Prive Counseling – Author Unknown  – The Cloud of Unknowing has long been a favorite to me. Recently I came across the Book of Prive Counseling. The Book of Prive Counseling was a relatively unknown until recently. It has since been associated with the same unknown abbot as the Cloud. Prive Counseling is a more mature work than Cloud of Unknowing. In this text we have the actual prive counsel of a mature contemplative in instructing one who is maturing. This text is not meant for all Christians, but the smaller subset of Christians who want to bask in the glory of God. 

I will add books from time to time as they provoke me, and as they become public domain.

Be well and may the grace of God be rich in you.