To take the case of Christianity as an example, the question of whether Mark (the evangelist) wrote the Gospel of Mark himself or was simply a translator for Peter is the subject of historical study.
キリスト教の例で言えば、「マルコ_(福音記者)がペトロの通訳であったかどうか、そのマルコが福音書を書いたかどうか」は歴史学の対象となる。