Your theory rests on very shakey ground, in my humble opinion. Y.(above) The correct name of the female Staple Singer whorocks this song in The Last Waltz is Mavis Staple, not Marva.
(The late "Pops" Staple's correct first name was Roebuck.)Hugh from Calgary, Canada.
Look at the stanzas one by one and you can clearly see each maps to a major event or figure in the NT.
Now I am not a religious man at all, but I do calls 'em as I sees 'em. Crazy Chester is Paul, or more generally Jesus' followers, but it could allude to Judas, 'the dog' being his sinfulness at betraying Jesus, who 'feeds his dog' by allowing it to happen.
Aretha Louise Franklin will celebrate her 74th birthday come next month on March 25th .
On September 7th 1969, "The Weight" by the Supremes and the Temptations entered the Hot Top 100 chart at position #69; and on September 21st, 1969 it peaked at #46 and spent 5 weeks on the Top 100... The pairing of the two super groups also produced two more Top 100 records; "I'm Gonna Make You Love Me" and "I'll Try Something New" .. Just a little background on the characters origins in this song. A neighbour of his was Chester, and when Ricky was old enough worked on the tobacco farm that Chester owned.
Not sure what exactly the lyrics mean about Jack in the story, but that is exactly the way crazy Chester talked. Some of the other characters were part of Chester's family (Luke, Emily, Carmen...).