Sayyiduna Ibn Umar (may Allah be pleased with them both) narrated from Sayyiduna Suhaib (may Allah be pleased with him) that he (Suhaib) passed by the Messenger of Allah (peace and blessings be upon him) and greeted him with salam while the Prophet (peace and blessings be upon him) was praying. The Prophet (peace and blessings be upon him) replied to the salam with a gesture. The narrator of the hadith, Layth, said: I think he said that he replied to the salam with a gesture of his finger.