  In the West knowledge of most of Aristotle's texts was lost, but not in the East. They were translated into Syriac, and Arabic, and eventually (in Muslim Spain) into Latin, and re-entered Christian Europe in the twelfth century accompanied by translations of the great Arabic commentaries. In the initial prophetic period of Islam (CE 610–32) the Qur'an was given to Mohammad, who explained it and reinforced it through his own teachings and practices. The notion of God's (Allah's) commands is again central, and our obedience to these commands is the basis of our eventual resurrection. Disputes about political authority in the period after Mohammad's death led to the split between Sunnis and Shiites. Within Sunni Muslim ethical theory in the Middle Ages two major alternative ways developed of thinking about the relation between morality and religion. The first, the Mu'tazilite, was given its most developed statement by ‘Abd al-Jabbar from Basra (d. 1025). ‘Abd al-Jabbar defines a wrongful act as one that deserves blame, and holds that the right and wrong character of acts is known immediately to human reason, independently of revelation. These standards that we learn from reason apply also to God, so that we can use them to judge what God is and is not commanding us to do. He also teaches that humans have freedom, in the sense of a power to perform both an act and its opposite, though not at the same time. (For Mu'tazilite ethical theory, see Sophia Vasalou, Moral Agents and Their Deserts: The Character of Mu'tazilite Ethics and George Hourani, Islamic Rationalism: The Ethics of ‘Abd al-Jabbar.) The second alternative was taught by al-Ashari (d. 935), who started off as a Mu'tazilite, but came to reject their view. He insists that God is subject to none and to no standard that can fix bounds for Him. Nothing can be wrong for God, who sets the standard of right and wrong. This means that ‘if God declared lying to be right, it would be right, and if He commanded it, none could gainsay Him’ (The Theology of al-Ash'ari, 169-70). With respect to our freedom, he holds that God gives us only the power to do the act (not its opposite) and this power is simultaneous to the act and does not precede it. A figure contemporary with al-Ashari, but in some ways intermediate between Mu'tazilites and Asharites, is al-Maturidi of Samarqand (d. 944). He holds that because humans have the tendency in their nature towards ugly or harmful actions as well as beautiful or beneficial ones, God has to reveal to us by command what to pursue and what to avoid. He also teaches that God gives us two different kinds of power, both the power simultaneous with the act (which is simply to do the act) and the power preceding the act (to choose either the act or its opposite). (For the work of al-Maturidi, see Ulrich Rudolph, Al-Maturidi and Sunni Theology in Samarkand.)