Language:
كتاب الأدب
78  
Good Manners and Form (Al-Adab)
(80)
Chapter: "Make things easy for the people and do not make things difficult for them."
(80)
باب قَوْلِ النَّبِيِّ صلى الله عليه وسلم: «يَسِّرُوا وَلاَ تُعَسِّرُوا»
Sahih al-Bukhari 6124

Narrated Abu Musa:

that when Allah's Messenger (ﷺ) sent him and Mu`adh bin Jabal to Yemen, he said to them, "Facilitate things for the people (treat the people in the most agreeable way), and do not make things difficult for them, and give them glad tidings, and let them not have aversion (i.e. to make the people hate good deeds) and you should both work in cooperation and mutual understanding, obey each other." Abu Musa said, "O Allah's Messenger (ﷺ)! We are in a land in which a drink named Al Bit' is prepared from honey, and another drink named Al-Mizr is prepared from barley." On that, Allah's Messenger (ﷺ) said, "All intoxicants (i.e. all alcoholic drinks) are prohibited."

حَدَّثَنِي إِسْحَاقُ، حَدَّثَنَا النَّضْرُ، أَخْبَرَنَا شُعْبَةُ، عَنْ سَعِيدِ بْنِ أَبِي بُرْدَةَ، عَنْ أَبِيهِ، عَنْ جَدِّهِ، قَالَ لَمَّا بَعَثَهُ رَسُولُ اللَّهِ صلى الله عليه وسلم وَمُعَاذَ بْنَ جَبَلٍ قَالَ لَهُمَا ‏"‏ يَسِّرَا وَلاَ تُعَسِّرَا، وَبَشِّرَا وَلاَ تُنَفِّرَا، وَتَطَاوَعَا ‏"‏‏.‏ قَالَ أَبُو مُوسَى يَا رَسُولَ اللَّهِ إِنَّا بِأَرْضٍ يُصْنَعُ فِيهَا شَرَابٌ مِنَ الْعَسَلِ، يُقَالُ لَهُ الْبِتْعُ، وَشَرَابٌ مِنَ الشَّعِيرِ، يُقَالُ لَهُ الْمِزْرُ‏.‏ فَقَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏"‏ كُلُّ مُسْكِرٍ حَرَامٌ ‏"‏‏.‏
Reference : Sahih al-Bukhari 6124
In-book reference : Book 78, Hadith 151
USC-MSA web (English) reference : Vol. 8, Book 73, Hadith 145
  (deprecated numbering scheme)