On a recent road trip I listen to several sermons. There were two by John Piper that really Bibled my mind (it's gonna be a thing, jump on the train before everyone else does) and were very challenging.
This first one is described as a "Biblical theology of singleness." John Piper looks at the topic of singleness across the Bible and shows both and and married life for what they are in view of God's eternal plan. :It's awesome, and challenged several notions that I held in the back of my mind.
This second one is entitled "Tongues of Fire and the Fullness of God." If I were to re-title it according to the point that was most meaningful to me, I would call it "The Sovereignty of the Holy Spirit." Either way, Piper examines how the Holy Spirit operated in Acts and deals with some tough passages. It gives a lot to think about and is very humbling.
The sermons are definitely worth your time. Here is a picture I took of daisies in a field.