If this isn't divine inspiration at work, I don't know what is. Part I of this disc (all 45 minutes of it, but particularly the middle 20) is perhaps the most beautiful music ever recorded--and it was (amazingly) improvised. While some of the (unfortunate) trademark Jarrett grunting and moaning is present throughout the two improvised pieces, in Part I it almost seems necessary. The piece is that powerful, moving, and beautiful. Give it a listen if you don't believe me, but be prepared to have goosebumps.
Part II is far more dissonant, but still incredible and at times as beautiful as part I. When you reach the end of these 73 minutes of improvised majesty, you almost need the stunning delivery of "Over the Rainbow" to bring you back down to Earth. And it is rendered as stunningly as I have ever heard.
This disc is essential for all lovers of piano music--both classical and solo jazz. Very Highly Recommended.