The present study seeks to answer the main question: "What is the relationship between the thinking of Al-Ghazali and Ibn Sina?" The key findings are as follows: The proximity of the eras in which Ibn Sina and Al-Ghazali lived led to some similarities between the two thinkers. The rulers during Ibn Sina's time were mostly Shiite or from moderate Sunni sects, whereas the rulers in Al-Ghazali's era held intense political biases. Consequently, Al-Ghazali's first period was marked by confrontation with philosophers; the writing of *The Incoherence of the Philosophers* as a refutation of philosophy and the act of declaring Ibn Sina an apostate, as the leading philosopher, are products of this period. Al-Ghazali's second period was characterized by doubt and perplexity, a phase not reported similarly for Ibn Sina. The third period represents Al-Ghazali's seclusion and late life, a time of greater focus on the heart, mystical revelation, and reduced sensitivity toward philosophers. In Ibn Sina's later years, there is also evidence of increased attention to mystical issues, although significant differences in content and practical approach exist between the two thinkers.