When one of you meets his brother, let him greet him with peace. If a tree, a wall, or a rock comes between them and then he meets him again, let him greet him with peace once more.Muawiya said, Abdul-Wahhab bin Bakht also narrated to me from Abu Zinad, from Araj, from Abu Hurairah, from the Messenger of Allah ﷺ the rider greets the one walking.
حدثنا أحمد بن سعيد الهمداني حدثنا ابن وهب قال أخبرني معاوية بن صالح عن أبي موسى عن أبي مريم عن أبي هريرة قال إذا لقي أحدكم أخاه فليسلم عليه فإن حالت بينهما شجرة أو جدار أو حجر ثم لقيه فليسلم عليه أيضا قال معاوية و حدثني عبد الوهاب بن بخت عن أبي الزناد عن الأعرج عن أبي هريرة عن رسول الله ﷺ مثله سواء
Sourcing, [sahih] Bukhari narrated it in Adab al-Mufrad, no. 1010, from the hadith of Muawiya bin Salih through the same chain, but he did not mention Abu Musa in the chain, and this Abu Musa is unknown. It has corroborating narrations with Ibn Sunni in Amal al-Yawm wal-Layla, no. 245, and Tabarani in al-Awsat, no. 7983, and others. See Nayl al-Maqsud 3/1078.