Originally Posted by
Cogitoergosum
Sorry, I haven't answered until now, but I've been busy, busy, busy
If one would say the sentence
"Hans ögon den djupaste brunn", it would sound weird.
The correct way to say it would be
"Hans ögon är som den djupaste brunn" (His eyes
are like the deepest well).
However, since she stated in the previous sentence that
his mind is like the sun, you don't really need to repeat the
är som/are like part in the next sentence (and thus making it grammatically correct) to understand what she means. I think she just skips that part to make the lyrics fit the melody.
When I first saw the lyrics, I interpreted them like this:
För hans sinne är som solen
'Cause his mind is like the sun
Hans ögon (är som) den djupaste brunn
His eyes (are like) the deepest well
I hope this helped. I'm not very good at explaining things, but I tried