Franz Kafka (3 July 1883 – 3 June 1924) was an influential German-language writer of novels and short stories, regarded by critics as one of the greatest authors of the 20th century. Kafka was a Modernist and heavily influenced other genres, including existentialism. His works, such as "Die Verwandlung" ("The Metamorphosis"), Der Process (The Trial), and Das Schloss (The Castle), are filled with the themes and archetypes of alienation, physical and psychological brutality, parent-child conflict, characters on a terrifying quest, and mystical transformations.
1.) Leavitt, June (2011). The Mystical Life of Franz Kafka: Theosophy, Cabala, and the Modern Spiritual Revival. Oxford University Press. p. 8. ISBN 978-0-19-982783-1. "Undoubtedly, synagogue life appalled Kafka, but not because he was an atheist. It appalled him because, in his words, he was trying to “build his faith,” and the conventional forms were not adequate."
2.) "Whilst Kafka had a brief interest in Kabbalah, mysticism, and Yiddish theatre, he rarely attended synagogue and considered himself an atheist." - Benjamin Lazarus, The Jewish Chronicle Online.