This is a translation in verse, so don't set too much store on the exact wording. Some of the words may have been chosen for rhythm and rhyme rather than for precise meaning.
For reference, here's the Latin original (or at least one of the preserved Latin texts, I don't know if we know what the exact original is):
Montis in excelsi scopulo, rex ...
Let Psyche’s body be clad in mourning wed,
And set on rock of yonder hill aloft:
Her husband is no being of human seed,
But serpent dire and fierce as might be thought.
Who flies with wings above in starry skies,
And doth subdue each thing with fiery flight.
The gods themselves, and powers that seem so wise,
With mighty Jove, be subject ...
In The Golden Ass, Cupid does not give any reason why explicitly. He simply forbid her:
But he gave her a further charge saying, Beware that ye covet not (being moved by the pernicious counsel of you sisters) to see the shape of my person, lest by your curiosity you deprive your selfe of so great and worthy estate.
When he realizes she disobeyed him, his ...