"They are kneeling."
Translation:De står på kne.
"står på kne" is the most common in present tense, but it seems "lå på kne" and "sto(d) på kne" are both common in past tense. Using 'lå' might be somewhat old-fashioned as you say, as it's from a fairytale. I'm not entirely sure if there really is a difference between 'lå' or 'sto(d)', I'd think they'd mean the same.