The Messenger of Allah ﷺ came to the Quba mosque to pray there. Some men from the Ansar came and greeted him with salaam.I asked Suhayb, who was with him, "How did the Messenger of Allah ﷺ return their greetings?"He replied, "He would gesture with his hand."
أتى رسول الله ﷺ مسجد قباء يصلي فيه. فجاءت رجال من الأنصار يسلمون عليه. فسألت صهيبا، وكان معه: كيف كان رسول الله ﷺ يرد عليهم؟ قال: كان يشير بيده.
Nasai (1187) and Ibn Majah (1017) both narrated it via Sufyan bin Uyayna, from Zayd bin Aslam, from Abdullah bin Umar, who mentioned the same. Ibn Khuzayma also narrated it via this same route in his Sahih (888). Abu Dawud (925), Tirmidhi (367), and Nasai (1186) all narrated it from Qutayba bin Saeed, who said, Layth bin Saad narrated to us, from Bukayr bin Abdullah bin Ashaj, from Nabil, the companion of the cloak, from Ibn Umar, from Suhayb, who said, "I passed by the Messenger of Allah ﷺ while he was praying, so I greeted him, and he returned the greeting to me with a gesture." He said, and I only know it as, he said, "with a gesture of his finger."In it is Nabil, who is not well known, as Nasai said. But he said elsewhere, "trustworthy," and Ibn Hibban mentioned him among the trustworthy narrators. Al-Hafiz said, "acceptable," meaning when corroborated, and he has indeed been corroborated. Tirmidhi said, "The hadith of Suhayb is hasan, we do not know it except through the hadith of Layth from Bukayr."As for his statement, "I only know it as, he said..." the one who said this is Layth bin Saad himself, as Darimi (1367) made explicit, after narrating it from Abu Walid, who is Tayalisi, who said, Layth bin Saad narrated to us with the same wording.The hadith has another chain of transmission, through Hisham bin Saad, who said, Nafi narrated to us, saying, I heard Abdullah bin Umar say, the Messenger of Allah ﷺ went out to Quba to pray there. He said, the Ansar came to him and greeted him while he was praying. He said, so I said to Bilal, "How did you see the Messenger of Allah ﷺ respond to them when they greeted him while he was praying?" He said, "He gestures like this," and he spread out his palm. And Jafar bin Awn spread out his palm, placing its inner side downward and its back upward.Abu Dawud (927) narrated this from Husayn bin Isa Khurasani Damaghani, who said, Jafar bin Awn narrated to us, who said, Hisham bin Saad narrated to us, and he mentioned the same. Tirmidhi (368) narrated it from Mahmud bin Ghaylan, who said, Waki narrated to us, from Hisham bin Saad, with the same content but in abridged form, and he said, "hasan sahih."He also said, the story in the hadith of Suhayb is a different story from that in the hadith of Bilal, and both hadiths, in my view, are sahih. Even though Ibn Umar narrated from both of them, it is possible that he heard from both of them together. End of quote.