Lyric discussion by PoetLunatic 

I don't know if Zevon knew he was going to die when he wrote this, but he was always known for his dry wit and his penchant towards death and the macabre. He may not have gotten his "death sentence" from the doctor (his lung cancer diagnosis), but his body could have been telling him something wasn't right. Or maybe it was Zevon being in his "spit in the eye of the reaper" mentality. As for the song, I believe it's about his last ride on this earth to heaven. The religious and romantic allusions are there.
We'll start there. Of course there's Jesus. The song refers to the movie (possibly book) "3:10 to Yuma" about a hero's journey to help transfer an outlaw to a train to the courthouse. The outlaw kept offering more money than the hero was going to get for the transfer. "I'll take the mazuma" (money) could mean Jesus was going to let him off the death train.
Charleton Heston (not dead at the time the song was written) was best known for playing Moses in "The Greatest Story Ever Told" ... before he was the NRA spokesman. I think Heston was a symbol for Moses in this song, a man who led his people to the land of milk and honey. In the song, he's slowing Zevon down to hear the "story" but Zevon is already on his way to glory and doesn't have time to listen. As for the Romantic poets : Shelley, Keats, and Lord Byron... the romantics were known for living life to the fullest and trying to feel all that is good. And these three all died much younger than normal for that time period. Yes, they were the "class of 27." *Class of 27 refers to the rockers like Jimi Hendrix, Jim Morrison, and Janis Joplin who died early due to their excesses at the age of 27. Shelley, Keats, and Byron all had short, brilliant careers followed with death. Byron, for instance, died of either flu or drowning in Greece. I don't think Zevon's reference towards them was ignorant of this fact. Plus they were known to enjoy their drink and their opium.
Other religious symbols such as wrestling with an angel (like Job, I believe) and the seraphim (thanks to Kevin Smith's Dogma, I know this means a member of the highest choir of angels) are also prevalent in the song.
Now I'm not Zevon, who is the only person who truly knows what the song means, but to me it sounds like he has heard his impending doom and is about to ride out to the sunset of heaven.

This is great and spot on...

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