Okay, maybe I need to add more.

The Bob Dylan refrain "where are you going my blue eyed son"
is taken from an English poem about a rich guy who is slowly dying because he was poisoned by his girlfriend who he was about to propose to. It called Lord Randall.
But the poem specifies, by repeating the blue eye color, that the person relating what he has seen is WHITE.

The white man walking a black dog could have many meanings, but just to note: They used to bury a black dog in a newly dug cemetery before they buried any people in it. The idea was that the dog would guard the cemetery. Also, in many cultures especially the British Isles, black dogs were associated with the devil or evil, and also a symbol of death.