How to clean an old wooden door?
I have purchased a vintage age wooden house entry door. It has multiple glass panels and original hardware. We are going to use it as a sliding barn door between two rooms in our basement -- more to offer privacy if someone wants to play XBox and others want to watch TV on our projector system. The door is in good shape, but is very dirty from storage over the years. It is unpainted but is stained, and I believe it has been poly-ed or otherwise varnished. I used plain water with Dawn and a scrub brush but it seems to not be removing the grime -- I literally wipe the surface with my hand after scrubbing and my hand is filthy. I don't want to use anything like a pressure washer as the glass would surely be broken. I am also hesitant to sand as this is going to remove the color and I would need to stain, etc. to restore.
So, do I clean as best I can and then varnish over the residual dirt? Any suggestions and product recommendations are welcome!