Language:
كتاب المناقب
61
Virtues and Merits of the Prophet (pbuh) and his Companions
(23)
Chapter: The description of the Prophet (saws)
(23)
باب صِفَةِ النَّبِيِّ صلى الله عليه وسلم
Sahih al-Bukhari 3560

Narrated `Aisha:

Whenever Allah's Messenger (ﷺ) was given the choice of one of two matters, he would choose the easier of the two, as long as it was not sinful to do so, but if it was sinful to do so, he would not approach it. Allah's Messenger (ﷺ) never took revenge (over anybody) for his own sake but (he did) only when Allah's Legal Bindings were outraged in which case he would take revenge for Allah's Sake.

حَدَّثَنَا عَبْدُ اللَّهِ بْنُ يُوسُفَ، أَخْبَرَنَا مَالِكٌ، عَنِ ابْنِ شِهَابٍ، عَنْ عُرْوَةَ بْنِ الزُّبَيْرِ، عَنْ عَائِشَةَ ـ رضى الله عنها ـ أَنَّهَا قَالَتْ مَا خُيِّرَ رَسُولُ اللَّهِ صلى الله عليه وسلم بَيْنَ أَمْرَيْنِ إِلاَّ أَخَذَ أَيْسَرَهُمَا، مَا لَمْ يَكُنْ إِثْمًا، فَإِنْ كَانَ إِثْمًا كَانَ أَبْعَدَ النَّاسِ مِنْهُ، وَمَا انْتَقَمَ رَسُولُ اللَّهِ صلى الله عليه وسلم لِنَفْسِهِ، إِلاَّ أَنْ تُنْتَهَكَ حُرْمَةُ اللَّهِ فَيَنْتَقِمَ لِلَّهِ بِهَا‏.‏
Reference : Sahih al-Bukhari 3560
In-book reference : Book 61, Hadith 69
USC-MSA web (English) reference : Vol. 4, Book 56, Hadith 760
  (deprecated numbering scheme)