I don't believe it was either Robert Plant's or Page's intention to glorify Satan, but the dark side seems to always reveal itself in unexpected, shadowy ways.
(Of course, this is conjecture on my part - but I found Plant's reaction to hearing the song just a little odd - even though he did manage an eye tear for it, overwhelmed at the sheer magnitude of effort that was put in to the performing presentation.) From all I've gathered and read concerning this song and the way it came about, I don't believe Robert Plant is comfortable with it and would rather not have to remember the song that ironically made them famous.Jesus said that Satan is the "prince of this world" and so it is.I'm not saying that Plant consciously understood that he was being influenced, but he was just the same.It is not coincidental listening to "Stairway" backwards that the name of "Satan" surfaces 6 times.The four of them together created a hauntingly, uncharted, wild and amazing sound. With that said there is no mistaking the symbolism embedded in Zep's albums.
My fave of theirs was "Kashmir" and "Immigrant"Now all this talk about the occult and back masking may sound very weird and possibly a boat load of silliness, however, one can not be attracted to the likes of Alleister Crowley (like Jimmy Page was) and not be drawn in to the darkness he lived within. Words and things have meaning and both Page and Plant meant them to have meaning.I got chills seeing the pre-9/11 Twin Towers/World Trade Center in the film just before Stairway To Heaven is performed.I remember the day the Towers were destroyed like it was yesterday, and seeing them still standing just before a moving song is about to be played breaks my heart all over again. And this song is about the NEW WORLD ORDER and new age/shift in consciousness: rise of the anti Christ. I have a deep respect for music in general and this song in particular.Likewise, music reflects the consciousness of its Creator(s) at the time it was created, along with their past experience and their intention, as expressed in the lyrics or performance.Sadly, both Plant, Page and Bonham paid a dear and painful price for what they permitted themselves to be influenced by (whether consciously or unconsciously), thus their fame and fortune -- because the angel of light will always demand some form of collateral exchange.