Does the song Stairway to Heaven contain Satanic messages?

Oh here's to my sweet Satan.
The one whose little path would make me sad, whose power is Satan.
He will give those with him 666.
There was a little tool shed where he made us suffer, sad Satan.^[1]

Personally, I couldn't really discern any of those words until I listened a few times.

The band, however, denies this claim.

Led Zeppelin audio engineer Eddie Kramer called the allegations "totally and utterly ridiculous. Why would they want to spend so much studio time doing something so dumb?" [Davis, Stephen. The Hammer of the Gods (1985) p. 335]

Robert Plant expressed frustration with the accusations in a 1983 interview in Musician magazine: "To me it's very sad, because 'Stairway to Heaven' was written with every best intention, and as far as reversing tapes and putting messages on the end, that's not my idea of making music."^[2]