While visiting the community, he saw a photograph of Rembrandt's "The return of the prodigal son", that made a deep impression on him. He decided to see the painting personally and traveled to Saint Petersburg (Leningrad at that time) to visit the Hermitage Museum where it is kept. This resulted in a several day contemplation of the painting, and the book of the same name, probably his most famous.
After a long period of declining energy, which he chronicled in his final book, Sabbatical Journey, he died in September 1996 from a sudden heart attack.
His spirituality was influenced notably by his friendship with Jean Vanier. At the invitation of Vanier, Nouwen visited L'Arche in France, the first of over 130 communities around the world where people with developmental disabilities live with those who care for them. In 1986 Nouwen accepted the position of pastor for a L'Arche community called "Daybreak" in Canada, near Toronto. Nouwen wrote about his relationship with Adam, a core member at L'Arche Daybreak with profound developmental disabilities, in a book titled Adam: God's Beloved. Father Nouwen was a good friend of the late Cardinal Joseph Bernardin.
The results of a Christian Century magazine survey conducted in 2003 indicate that Nouwen's work was a first choice of authors for Catholic and mainline Protestant clergy.
One of his most famous works is Inner Voice of Love, his diary from December 1987 to June 1988 during one of his most serious bouts with clinical depression.
Prior to his death in 1996, Nouwen entrusted Sue Mosteller with his estate, making her the literary executrix of his works.
One of Nouwens' major ongoing themes involved his struggle reconciling his depression with his Christian faith. In Return of the Prodigal Son, for example, Nouwen describes love and forgiveness as unconditional. In that book, he invites the reader to follow him in his personal return to the spiritual fountains, and a parallel meditation on all the characters of the parable, and their rendering by Rembrandt, and the painter's personal life.
Nouwen also wrote several essays on the necessity of peacemaking. He used God's Love as a justification for the preservation of life, as well as saying "No" to both the Vietnam and Nuclear War[weasel words].
His struggle to reconcile his priestly vows of celibacy with his human desire for physical and emotional intimacy was also a theme in his writings.
Thomas Merton Award, given to national and international individuals struggling for justice in 1985.
Nouwen is thought to have struggled with his sexuality. "Although his homosexuality was known by those close to him, he never publicly claimed a homosexual identity." Although he never directly addressed the matter of his sexuality in the writings he published during his lifetime, it is said that he acknowledged the struggle both in his private journals and in discussions with friends, both of which were extensively referenced by Michael Ford in the biography Wounded Prophet, which was published after Nouwen's death. Ford suggests that Nouwen only became fully comfortable with his sexual orientation in the last few years of his life, and that Nouwen's depression was caused in part by the conflict between his priestly vows of celibacy and the sense of loneliness and longing for intimacy that he experienced. Ford conjectured, "This took an enormous emotional, spiritual and physical toll on his life and may have contributed to his early death." There is no evidence that Nouwen ever broke his vow of celibacy.
Nouwen, Henri. “Resisting the Forces of Death” & “'No' to the Vietnam War” in Liberating Faith: Religious Voices for Justice, Peace, and Ecological Wisdom. Ed. Roger S. Gottlieb. Lanham, Maryland: Rowman & Littlefield, 2003. 467-475.
Nouwen, Henri J. M. (1994). Here and Now, Living in the Spirit. Darton, Longman and Todd Ltd. ISBN0-232-52092-5.
Nouwen, Henri J. M. (2002-08-01). Life of the Beloved: Spiritual Living in a Secular World. The Crossroad Publishing Company; 10 Anv edition. ISBN0-8245-1986-8.
Nouwen, Henri J. M. (1999-01-19). The Inner Voice of Love: A Journey Through Anguish to Freedom. Image Books. ISBN978-0-385-48348-3.