About whom was Leonardo speaking? About himself? I don’t recall his biography being full of episodes of his punishing those he considered evildoers.
Or is he speaking about God, who is not visibly punishing the evil acts we see all around, but rather, allowing them to occur.
Sorry, don’t know any background; I just took the quote on its face.
But Fr. Rutler’s reference to “Be opened.”, and the Da Vinci quote reminds us that if we live in moral silence, we are aiding and abetting evil.