Either he got words from a book or somebody half-remembered a record. Either way he had a good preacher verse
Well hear the preacher preach
Pass his hat around
Cryin' Brothers and sisters leave your money to me
I'm Alabammy bound
The verse is from Leadbelly.
I suspect one of Lonnie Donegan's sources was this recording that Leadbelly made with backing by Woody Guthrie and Cisco Houston.
Personally I think he sounds better with these white folkies than he does with the black Golden Gate Quartet. The latter were more polished musicians, but didn't have the enthusiasm and deep respect that Woody and Cisco had. At least one of the Quartet spoke rather disparagingly of Leadbelly in an interview.
For both recordings he uses the same arrangement featuring the melody line on his guitar in unison with his voice or just solo. Many musicians since have copied this.
And he uses more or less the same verses ? though only the recording with Woody and Cisco has an
Elder Green verse.
By contrast, when he recorded the song for the Library of Congress in 1935, he hadn't worked up the arrangement. And he was a bit stuck for verses. I suspect he subsequently picked up some verses from the Lomaxes.