"King Darius Suite"
This starts with a quotation of Mozart's Serenade No. 13 in G major, K. 525 (albeit in Eb major), commonly referred to as Eine kleine Nachtmusik (literally, a little night music). Since "King Darius Suite" is about King Darius' dream (there are two in the Bible: in Daniel 2 and Daniel 4) and dreams usually occur at night, that quotation helps to set that nighttime context.
"We are the Grapes of Wrath"
I think I was dimly aware that this is a reference to John Steinbeck's book The Grapes of Wrath, and apparently Steinbeck's title alludes to Revelation 14:17-20 (so, it's an allusion upon an allusion). Listening to it this time, however, I noticed this stanza:I'm ma; I'm pa; this is our broodThe names here are the same names from Steinbeck's book! I've read The Grapes of Wrath only once (and that was almost three years ago now), but - if I remember correctly - the parents are referred to only as "Ma" and "Pa." The main character is Tom Joad, and his sister is named Rose of Sharon (although it's rendered as "Rosasharn" when it appears in dialogue).
We're grumpy, and we know it
That's Tom and Rosie; they're both rude
And not afraid to show it
