(Arabic: “assimilating”), in Islām, anthropomorphism, comparing God to created things. Both tashbīh and its opposite, taʿṭīl (divesting God of all attributes), are regarded as sins in Islāmic theology. The difficulty in dealing with the nature of God in Islām arises from the seemingly contradictory views contained in the Qurʾan (Islāmic scripture). On the one hand God is described as unique and not similar to anything that the mind can imagine; on the other hand he is referred to in the language of anthropomorphism—having eyes, ears, hands, and face, and sitting on his throne and talking and listening.

Some Muslim theologians argued that the Qurʾān used such human concepts and idioms because there are no other means of delivering God's message to man and urged that they be interpreted allegorically rather than literally. Al-Ashʿarī, a 10th-century Muslim theologian, asserted that the hands, eyes, and face of God and his sitting and talking must be recognized literally without asking how.

In the literature of the Ṣūfīs (Muslim mystics) God is spoken of in the language and style of ordinary love poetry, which the Ṣūfīs interpret allegorically. This is done on the grounds that man is created after God's own image. When Ibn al-ʿArabī (Muslim mystic of the 12th century) published his collection of poems Tarjumān al-ashwāq (“The Interpreter of Desires”), the Muslim orthodox rejected his claim of alluding to divine realities and accused him of actually celebrating the charms of his mistress. He wrote a lengthy interpretation of the poetic text to avoid the accusation of tashbīh.

Both tashbīh and taʿṭīl were avoided by many theologians who spoke rather of tanzīh (keeping God pure) and of tathbīt (confirming God's attributes). The major reason for the fear of tashbīh is that it can easily lead to paganism and idolatry, while taʿṭīl leads to atheism.