The first book of young Elie Wiesel, never published, was finally found. This book deals with asceticism and was directly influenced by his master Shushani (or Monsieur Chouchani in French).
The myster.

“Shushani” – wrote Wiesel in his book (“All Rivers Run to the Sea,” page 150) “led me surreptitiously to a subject that had always fascinated me: asceticism, the lure and quest for suffering, the will to suffer so as to infuse one’s own suffering and that of others with meaning. We talked of the ascetic and his self, enriched or mutilated by suffering, the relation between suffering and truth, suffering and redemption, suffering and spiritual purity, suffering as a gateway to the sacred, the prophetic, rabbinical, mystical point of view. Was it necessary, even indispensable, to punish the body in order to allow the soul to soar to new heights? Why was the nazir (ascetic) considered a sinner in Scripture? Why was he compelled to bring a sacrifice to the Temple? How to understand the variety of ascetics?” (p. 150).

Read more here: https://www.jpost.com/Jerusalem-Report/Elie-Wiesels-first-book-574677?fbclid=IwAR0ZUcY-f89uaF4wLw4qJeq9asyTdttiQZS8qoVUolaOot10hireqFCDM_0