In Hinduism and Buddhism, meditative retreats are seen by some as an intimate way of deepening powers of concentration and insight.
Retreats are also popular in Christian churches, and were established in today's form by St. Ignatius of Loyola (1491-1556), in his Spiritual Exercises. Ignatius was later to be made patron saint of spiritual retreats by Pope Pius XI in 1922. Many Protestants, Catholics and Orthodox Christians partake in and organize spiritual retreats each year.
Meditative retreats are an important practice in Sufism, the mystical path of Islam. The Sufi teacher Ibn Arabi's book Journey to the Lord of Power (Risālat al-Anwāar) is a guide to the inner journey that was published over 700 years ago.