Abū Ḥāmid Muḥammad ibn Muḥammad al-Ghazālī, more commonly known as Imam Al-Ghazali, was a 5th century scholar of Islam. Referred to by the unique title of hujjat al-Islam, or the "proof of Islam", he is also considered to be the reviver of the faith of his time. (The Prophet pbuh said every century will have a reviver of the faith.) His works were studied (and continue to be studied) by Muslims and non-Muslims alike.
Here is an excerpt from Sheikh Ibrahim Osi-Efa relating Al Ghazali's story, a story which inspired and continues to inspire millions of Muslims to this very day...