Al-Adab Al-Mufrad, Book 21, Hadith 10 (In-Book) ⓘ
Ibn 'Abbas reported that the Messenger of Allah, may Allah bless him and grant him peace, said, "Do not dispute with your brother. Do not make fun of him. Do not make a promise to him and then break it."
حَدَّثَنَا عَبْدُ اللهِ بْنُ سَعِيدٍ، قَالَ: حَدَّثَنَا عَبْدُ الرَّحْمَنِ بْنُ مُحَمَّدٍ الْمُحَارِبِيُّ، عَنْ لَيْثٍ، عَنْ عَبْدِ الْمَلِكِ، عَنْ عِكْرِمَةَ، عَنِ ابْنِ عَبَّاسٍ قَالَ: قَالَ رَسُولُ اللهِ صلى الله عليه وسلم: لاَ تُمَارِ أَخَاكَ، وَلاَ تُمَازِحْهُ، وَلاَ تَعِدْهُ مَوْعِدًا فَتُخْلِفَهُ.
also referenced under: Hadith 394 (Reference) & Book 21, Hadith 394 (English)