Scimitars are a type of cutting weapon, more properly called shamshirs or saifs. One is pictured, along with the Shahaddah, on the Saudi flag. Symbolically, they stand for military power. A saying has it that Islam "flourishes in the shadow of the sword," meaning that Islam should have the military strength to impose religion on the unwilling, and to maintain it against the discontent. It's an attitude strange to the modern West, which generally holds that religion is a personal matter and not a function of government. Islamic belief differs: there, the function of the state is to enforce the religion, and the sword, or scimitar, is the instrument of enforcement.