In the poem ‘O Fortuna’ (anon., 13th c., but made famous by Carl Orff’s setting), there is this verse:
Quod per sortem
sternit fortem
mecum omnes plangite!
This is typically translated as ‘since luck strikes down the strong, everyone, weep with me!’ or something to that effect. I am confused about the use of ‘per sortem’ (prep.+acc.) for what seems to be the subject of the quod-clause. At first I thought it was some form of passive voice, but sternit is conjugated in the active.
I cannot seem to find any other examples of this usage of quod per. Is it even grammatical?