Spirit Within And Spirit Upon

What is the purpose of the baptism in the Holy Spirit? Do believers who are not Spirit-filled have the Holy Spirit? What does it mean to "walk in the Spirit"?
 
In The Spirit Within & The Spirit Upon, Rev. Kenneth E. Hagin answers these and other questions as he shows that the New Birth and the baptism in the Holy Spirit are two separate and distinct works of the Spirit of God.
 
Chapter titles include: 
"The Dual Working of the Holy Spirit"
"Suffering Unto Perfection"
"A Deeper Dimension"
"The Dwelling Places of the Spirit"
"The Importance of Walking in Love"