*The collection of Forty Hadith by al-Imam alNawawi (or Imam Nawawi) has been known, accepted and appreciated by Muslim scholars for the last seven centuries. Its significance lay in the fact that these selected forty hadiths comprise the main essential and fundamental concepts of Islam which, in turn, construct the minimum level of required revealed knowledge for every single Muslim.
*This is the book of the Islamic scholar Yahia bin Sharaful-Deen An-Nawawi . The book is now known as "An-Nawawi's Forty Hadiths". This is a popular small book in which the author gathered forty two of the sayings of prophet Muhammed salla Allah u alihi wa sallam.