Sticky Note:  The Holy Spirit makes current, the past work of Jesus

The Holy Spirit is the Spirit of Jesus himself, living within a believer...
    -giving life and power
    -purifying
    -revealing and teaching
    -leading personally
    -assuring and comforting
    
The Holy Spirit is a person, with whom we are in relationship.  This is the Person who is "literally" closer to us than anyone.  We listen to the Spirit, speak with the Spirit, enjoy the Spirit.  We can also grieve the Spirit, like we can grieve anyone we love and are in relationship with.

Ultimately, the Holy Spirit is working in us so that we enjoy and take advantage of all the benefits Jesus Christ won for us 2,000 years ago, and is changing us (whether we know it or not) to be like Jesus, in His life and mission.  Only He can do that.