(15) باب الرَّجُلِ يَضَعُ خَشَبَةً عَلَى جِدَارِ جَارِهِ
'Ikrimah bin Salamh narrated that :
there were two brothers from among the sons of Mughirah. One of them swore an oath to set a slave free if the other one fixed a piece of wood to his wall. Mujammi' bin Yazid and many men from among the Ansar came and said: "We bear witness that the Messenger of Allah (ﷺ) said: 'None of you should refuse to let his neighbor fix a piece of wood to his wall.' " He said: 'O my brother, judgment has been passed in your favor against me, but I have sworn an oath.' So go ahead and fix your wood to my wall."
Reference: Sunan Ibn Majah 2336
In-book reference: Book 13, Hadith 29
English translation: Vol. 3, Book 13, Hadith 2336