The Ihya's lasting historical importance lies substantially in this reconciling function: after its wide circulation, mainstream Sunni orthodoxy increasingly treated moderate Sufi practice as a legitimate, even necessary, complement to legal and theological learning rather than as a suspect deviation from it, a shift historians of Islam credit al-Ghazali's work with doing more than any other single book to accomplish. It remains, alongside the Quran and the major hadith collections, among the most widely read and cited works in the entire history of Islamic religious literature, still assigned in traditional centers of learning and still printed in countless editions and abridgments across the Muslim world.
The book's influence extended well beyond specifically Sufi circles, shaping mainstream Sunni devotional and ethical writing broadly, and its detailed treatment of specific vices and virtues, pride, envy, patience, gratitude and many others, gave later writers a durable framework for ethical instruction independent of its more explicitly mystical passages. Al-Ghazali himself regarded the Ihya as the summation of his mature thought, superseding much of his earlier, more purely philosophical and legal writing.