Why did Allah ordain Zakat?

Allah legislated Zakat for great wisdoms that encompass the giver, the receiver, and society. For the giver, it purifies him from stinginess and avarice, trains him in generosity, is an act of gratitude to Allah, purifies his wealth, and causes it to grow. As for the receiver, it enriches him, preserves his life, and purifies his heart from envy. For society, it establishes the general interests of Muslims, strengthens the religion, supports the weak and the reformers, eliminates the accumulation of wealth in a few hands, and prevents grudges, thus serving as a safety valve for Muslim society.