Volume 2 · Book 23 · Hadith 332
Narrated Abu Huraira: I heard Allah's Apostle saying, "The rights of a Muslim on the Muslims are to follow the funeral processions, to accept invitation and to reply the sneezer. (see Hadith No 331)
— Sahih Bukhari, Volume 2, Book 23: Funerals (Al-Janaa'iz), Hadith #332