On what basis is Zakat obligatory and to whom is it restricted?

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Zakat is obligatory upon the wealthy as an act of compassion for the poor and as gratitude for the blessing of affluence. The Prophet, peace be upon him, commanded, 'I have been ordered to take the Sadaqah from your wealthy and return it to your poor.' This indicates that it is incumbent only upon the wealthy and distributed only to the poor. The debtor is in need akin to, or more so than, the poor person, and it is not wise to neglect the need of the owner to fulfill the need of another. Moreover, the debtor has not achieved the state of wealth that necessitates the expression of gratitude through disbursement. The Prophet, peace be upon him, stated, 'Begin with yourself, then those you support.'