That looks good to me, although I don't quite get the lackofspace for the adjectives.
I have learned that if you have a list of words you can jam them together and then tack the enclitic
-que on the end.
But maybe that is more so for nouns – would it make more sense to put a space between the two adjectives here?
In sententious phrases it is common to omit the copula (est), but it's fine to leave it in.
I think I will leave it in for clarity, but thanks for mentioning that.
I might also suggest superus or excelsus for 'high', of which the former connotes 'divine (celestial, dwelling in the remote skies)' & the latter, being a participle, means 'raised (as if from a lower starting point)'.
I like the grandeur of these words –
altum is a little more standard.
Among the two you suggested, I think
excelsus fits better – I never felt that this quote implied shedding your nature and becoming divine.
However, it definitely invokes a feeling of rising to something higher, and
excelsus definitely captures that feeling.
Is it Aslan who says this?
Interestingly, it isn't – there are actually two different characters who say it.
First is the magician, Uncle Andrew, who says it to his nephew Digory (the protagonist mentioned in the title).
Second is the mysterious queen, Jadis, who ultimately becomes the White Witch in the second book.
It's been a long time since I read the story, but if I remember correctly, Digory was kind of creeped out by these two vastly different individuals using these same exact words.