(67) باب الإِخَاءِ وَالْحِلْفِ
Narrated Anas:
When `Abdur-Rahman came to us, the Prophet (ﷺ) established a bond of brotherhood between him and Sa`d bin Ar-Rabi`. Once the Prophet (ﷺ) said, "As you (O `Abdur-Rahman) have married, give a wedding banquet even if with one sheep."
Reference: Sahih al-Bukhari 6082
In-book reference: Book 78, Hadith 110
USC-MSA web (English) reference(deprecated numbering scheme): Vol. 8, Book 73, Hadith 105