Imam al-Nawawi was a scholar in many different disciplines of Islamic studies. The vastness of his works in these different areas is so great that if an individual decides to study fiqh, hadith, spirituality, or Quran; one would need to pass through Imam al- Nawawi. Along with the 40 Hadiths, he authored Riyad al-Saliheen, Al-Adhkar, and commentary of Sahih Muslim and Sahih Bukhari.
Imam al-Nawawi was one of the foremost figures of the Shafi’ madhab and the largest and most substantial book he wrote in this regard is called Al Majmua’ which is about 30 volumes. It is a work of comparative fiqh because he brings all of the opinions of different madhab’s on different issues together.