Abu Hamid Muhammad ibn Muhammad at-Tusi al-Ghazali borned 1058 in Tus, Iran, and died Dec 18 1111, Tus, was a great Muslim philosopher-theologian who was deeply influenced by the Sufis. He great work, Ihya` 'ulum ad-din ("The Revival of the Religious Sciences"), firmly established the right of the Sufis within Muslim orthodoxy. "The key to happiness is following the Sunna and imitating Allah's messenger in all his goings out and comings in, in his movements and times of rest, even in his way of eating, his manners, his sleep, and his speech... So you must sit while putting on trousers and stand while putting on a turban. You must begin with the right foot when putting on your sandals, and eat with your right hand..." More about him from Britannica Online.
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