For Etty Hillesum, the most important skill to be learned in the spiritual life was the skill of listening. In one of her last letters from the transit camp before she was put on the train for Auschwitz, she wrote to a friend, ‘Things come and go in a deeper rhythm, and people must be taught to listen; it is the most important thing we have to learn in this life.’ On 17 September 1942, aware of her own exhaustion in the midst of that terrible war, she wrote:
Even if one’s body aches, the spirit can continue to do its work, can it not? It can love and ‘hearken unto’ itself and others and unto what binds us to life. Truly my life is one long hearkening unto myself and unto others, unto God. And if I say that I hearken, it is really God who hearkens inside me. The most essential and the deepest in me hearkening unto the most essential and deepest in the other. God to God.