Thinking today of a haunting, beautiful tune ... I believe I've shared it here before, but it deserves another feature.  "Eli Eli" is a poem written by Hannah Szenes / Senesh ... and this tells the story better than I could:

Eli Eli

This is a piece that drifts in and out of my repertoire, because my version is vocal - I don't have an instrumental-only rendition - and I don't get to sing at most of my gigs.  I truly adore it, however, and each time coming back to it is another rush of beauty.