Shaykh al-Islām Taqī al-Dīn Abū al-‘Abbās Ahmad ibn ‘Abd al-Halīm ibn ‘Abd al-Salām Ibn Taymiyya—may Allah have mercy on him—replied:

In the name of Allah, the Most Merciful, the Especially Merciful.

All praise is due to Allah, Lord of the worlds. What is contained in the book “Fusūs al-Hikam” (The Bezels of Wisdom), and in similar writings, is unbelief in both its inward and outward meanings; its inward meaning is more abhorrent than its outward meaning. This is known as the doctrine of the proponents of the oneness of existence, divine indwelling, and union. They call themselves “those who have attained true realization.”

These people are of two types:

One type professes this without qualification. Such is the doctrine of Ibn ‘Arabī, the author of the Fusūs, and others like him, including Ibn Sab‘īn, Ibn al-Fārid, al-Qūnawī, al-Shushtarī, al-Tilimsānī, and their like, who say that existence is one. They say that the existence of the creation is the existence of the Creator. They do not acknowledge two beings, one of which created the other. Rather, they say: “The Creator is the creation, and the creation is the Creator.”