The Messenger of Allah ﷺ said, "When one of you meets his brother, let him greet him with salaam. If a tree, wall, or stone comes between them and then he meets him again, let him greet him with salaam once more."
قال رسول الله ﷺ: من لقي أخاه فليسلم عليه، وإن حالت بينهما شجرة أو حائط أو حجر ثم لقيه فليسلم عليه.
Abu Dawud (5600), Abu Yaala (6351), and Tabarani in Musnad Shamiyin (2072) all narrated it via Muawiya bin Salih, from Abdul-Wahhab bin Bakht Makki, from Abu Zinad, from Araj, from Abu Hurairah, who related it. The wording given is that of Tabarani, while Abu Dawud and Abu Yaala referred its wording to the wording of the stopped (mawquf) version, as will follow. Its chain is hasan because of Muawiya bin Salih (that is, ibn Hudayr), for his hadith is hasan.It was also narrated from Abu Hurairah as a stopped (mawquf) report. Abu Dawud (5200), Bukhari in Adab al-Mufrad (1010), and Abu Yaala (6350) all narrated it via Muawiya bin Salih, from Abu Maryam, from Abu Hurairah, who said, "When one of you meets his brother, let him greet him with peace. And if a tree, a wall, or a rock comes between them and he then meets him again, let him greet him with peace again."Its chain is hasan because of Abu Maryam, who is the Ansari, for he is truthful (saduq). The ruling belongs to the version with a connected chain (marfu), so it may be that Abu Hurairah used to relate it in both forms.