Al-Jahiz (Arabic: الجاحظ) was a Muslim polymath who lived during the Islamic Golden Age in the 8th and 9th centuries CE. He is best known for his work, Kitāb al-Ḥayawān (The Book of Animals), which tackles aspects of biology and zoology like animal classification, food chains and evolution. He was also one of the most influential non-Arab intellectuals and scholars in the Abbasid Caliphate. Some writers describe him as a freethinker.
Known for his witty style and mastery of Arabic prose, he is considered a founder of the adab literary tradition, which focuses on literature, culture, and eloquence. Al-Jahiz also belonged to the Mu'tazila school of theology and was close to the Abbasid caliph al-Ma'mun.
Al-Jahiz was one of the earliest Muslim authors to use Biblical material in Arabic translation. In his work Al-Radd 'alā al-Naṣārā, he said that the Hebrew Bible was trustworthy and more reliable than the Christian Gospels. He also rejected Jewish translations of the Old Testament when Christians used them to argue that Jesus was the literal Son of God. Al-Jahiz said that the parts of these translations that made God seem human came from poor translation, not from the original text. He accepted the Old Testament as valid in principle.