to fly in the air, as do enlightened men, is delightful and very natural to all of us – when we become pure.
Seen from the man of ignorance, this is superstition, fiction, silly imagined stories made up by naïve men.
Gandur is a goose, a gander, sometimes used poetically for a horse also,
and reið here a vehichle.
We take on a swan-guise, fjaðurhamur (feather-guise), which only needs our purity to really work for flying.
In Sanskrit hamsa is a swan, becoming Icelandic hamur (the skin of a bird),
hamur is also used metaphorically: komast í ham, gain super-powers to perform actions or speak up boldly.
We see nothing queer with using this in common everyday language, komast í ham.
But when it comes to flying we all of a sudden become stubbornly blind: man cannot fly by getting into hamur, rationally not.
Listen to pronunciation: gandreið fjaðurhamur,