Wahdat al-wujūd (Arabic: وحدة الوجود "unity of existence, oneness of being") is a doctrine in the field of Islamic philosophy and mysticism, according to which the monotheistic God is identical with existence (wujūd) and this one existence is that through which all existing things (mawjūdāt) exist. This doctrine, which in recent research is characterized as ontological monism, is attributed to the Andalusian Sufi Ibn Arabi (d. 1240) but was essentially developed by the philosophically oriented interpreters of his works. In the Early Modern Period, it gained great popularity among Sufis. Some Muslim scholars such as Ibn Taymiyya (d. 1329), ʿAbd al-Qādir Badā'ūnī (d. 1597/98) and Ahmad Sirhindi (d. 1624), however, regarded wahdat al-wujūd as a pantheistic heresy in contradiction to Islam and criticized it for leading its followers to antinomianist views. In reality, however, many advocates of wahdat al-wujūd emphasized that this teaching did not provide any justification for transgressing Sharia. The Egyptian scholar Murtada al-Zabidi (d. 1790) described wahdat al-wujūd as a "famous problem" (masʾala mashhūra) that arose between the "people of mystical truth" (ahl al-ḥaqīqa) and the "scholars of the literal sense" (ʿulamāʾ aẓ-ẓāhir). The Ni'matullahi master Javad Nurbakhsh (d. 2008) was of the opinion that Sufism as a whole was essentially a school of the "unity of being".
Another name for this doctrine is Tawhid wujūdī ("existential monism, doctrine of existential unity"). The adherents of Wahdat al-Wujūd were also known as Wujūdis (Wujūdīya) or "people of unity" (ahl al-waḥda).
