Hugo Steiner Prag: another version of the monk Medardus (The Devil’s Elixir), ca 1920.
Medardus is the monk in ETA Hoffmann’s The Devil’s Elixir (1816), pious at the beginning just like Ambrosio in The Monk but after he discovers a flask that contains an elixir he is tempted to drink and his life changes instantly. He causes desperation wherever he walks, encounters people who very much look like him, etc. It was of course inspired by The Monk but also by a tale by Christiane Benedikte Naubert where we find a monk of that name, tale which in turn may have inspired Lewis. In general, Medardus is the name of a French bishop of the 6th century who later was canonized.