Good Manners and Form (Al-Adab)
حَدَّثَنَا أَبُو الْوَلِيدِ، حَدَّثَنَا شُعْبَةُ، عَنْ مُخَارِقٍ، سَمِعْتُ طَارِقًا، قَالَ قَالَ عَبْدُ اللَّهِ إِنَّ أَحْسَنَ الْحَدِيثِ كِتَابُ اللَّهِ، وَأَحْسَنَ الْهَدْىِ هَدْىُ مُحَمَّدٍ صلى الله عليه وسلم.Narrated Tariq:`Abdullah said, "The best talk is Allah's Book (Qur'an), and the best guidance is the guidance of Muhammad
From Sahih al-Bukhari, whose reports the scholars accept as authentic.