One of Islam’s five canonical pillars is a predictable, fixed, and mildly progressive tax system called zakat. It was meant to finance various causes typical of a pre-modern government. Implicit in the entire transfer system was personal property rights as well as constraints on government—two key elements of a liberal order. Those features could have provided the starting point for broadening political liberties under a state with explicitly restricted functions. Instead, just a few decades after the rise of Islam, zakat opened the door to arbitrary political rule and material insecurity. A major reason is that the Quran does not make explicit the underlying principles of governance. It simply outlines the specifics of zakat as they related to conditions in seventh-century Arabia.