Without literature and writing, Jaromir wouldn't have his "secret miracle." And without his secret miracle, we wouldn't have "The Secret Miracle." Our buddy Borges loves to write about writing and this story is no exception. After all, our protagonist is a writer, and he is preoccupied with the "problematic pursuit of literature," seeking to redeem his lackluster career through the completion of one last play. But since Borges is always getting all universal on us, it's important to think about the bigger picture: this story examines what it means to be dissatisfied with the act of writing, what it means to suffer for one's art, and how it feels when the ideas finally start flowing. You know the drill.
Sure, it leads to his arrest and execution by the Nazis, but Jaromir's writing is mainly "problematic" because it makes him super anxious and obsessive.
If Jaromir is a product of God's imagination, this means that he gets to be a God-like figure in relation to the characters in his own play.