It's an 'imprecise' translation of the original sentence.
The passage had been translated 'imprecisely'.
an 'imprecise' description
(..) Something happened to you in Algeciras and you have not been the same. What happened to you? I wish I could say. Why don't you try? I don't want to be imprecise. ~ It's not a riddle. ~ No. It's a truth. I just don't know what the truth is. The gods haven't revealed it to me. (..)2017 TvShow: Vikings Title: Revenge Season: 4 Episode 18