(65) Prophetic Commentary on the Qur'an (Tafseer of the Prophet (pbuh))
كتاب التفسير
(5) "Show forgiveness, enjoin what is good, and turn away from the foolish (i.e., don't punish them)." (V.7:199)
Sahih al-Bukhari 4643 

Narrated `Abdullah bin AzZubair:

(The Verse) "Hold to forgiveness; command what is right..." was revealed by Allah except in connection with the character of the people.

حَدَّثَنَا يَحْيَى، حَدَّثَنَا وَكِيعٌ، عَنْ هِشَامٍ، عَنْ أَبِيهِ، عَنْ عَبْدِ اللَّهِ بْنِ الزُّبَيْرِ، ‏{‏خُذِ الْعَفْوَ وَأْمُرْ بِالْعُرْفِ‏}‏ قَالَ مَا أَنْزَلَ اللَّهُ إِلاَّ فِي أَخْلاَقِ النَّاسِ‏.‏
Reference : Sahih al-Bukhari 4643
In-book reference : Book 65, Hadith 165
USC-MSA web (English) reference : Vol. 6, Book 60, Hadith 167
  (deprecated numbering scheme)