Lyric discussion by TBrocks13 

If I'm not mistaken (or if I remember well), Brian May said he dreamed of the Great Flood (Bible episode) and decided to write a song about it. There's some parts that seem very obvious to me, linked to the Great Flood.

[Oh Oh people of the earth Listen to the warning The seer he said Beware the storm that gathers here Listen to the wise man.]

The seer/prophet is Noah. He is also the wise man seeing as he knows that a "storm [will] gathers here" because God told him so.

[Oh Oh children of the land Quicken to the new life Take my hand Fly and find the new green bough Return like a white dove]

The "new life" is probably the after-flood and there's the green bough and the white dove, which are well known symbols/elements of the Great Flood.

[Oh Oh - and two by two my human zoo They'll be runnung for to come running for to come out of the rain]

"two by two" is an obvious referrence to the saving of a male and female of every species, althought I'm not quite sure why it's a "human zoo", I'm not a Bible expert, but I think Noah and his family were the only humans that were saved from the flood. Maybe Noah and his family are God's "human zoo"?

[Oh Oh children of the land Love is still the answer, take my hand The vision fades, a voice I hear Listen to the Madman!

But still I fear and still I dare not Laugh at the Madman.]

The madman, who is it? I believe it's still Noah. But it said he was the "wise man", the "prophet"... but prophets are often believed madmen or fools. Noah is a wise man because he knows what is about to happen, but he's also a madman from the other human's perspective as they may not believe his warning ("Listen to the warning the prophet he said").

But still, they dare not laugh at the madman... maybe they believe he could not be wrong, they are struggling between believing him or not.

As for the echo/opera chants, they sound almost like religious chants (at least, that's how I perceive them).

The other parts of the song I didn't mentioned, I'm not quite sure how they could be linked with the Great Flood, so I prefer to step back for those.

But anyway, wether I'm right, partially right/wrong or completely in the wrong, it doesn't matter. This song is a true musical masterpiece, this is Brian May's "Bohemian Rhapsody".

@TBrocks13 - i think that is a very accurate interpretation

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