Musnad Ahmad 482:97

Muhammad ibn Ubayd narrated to us, Muhammad—meaning Ibn Ishaq—narrated to us, Yazid ibn Abi Habib narrated to me, from Marthad ibn Abdullah al-Yazani, from Abu Abd al-Rahman al-Juhani, who said: While we were with the Messenger of Allah, may Allah bless him and grant him peace, some riders appeared. When he saw them, he said: "Two men from Kinda, from Madh-hij," until they came to him, and they were indeed men from Madh-hij. He said: One of them drew near to him to pledge allegiance to him. He said: When he took his hand, he said: "O Messenger of Allah, what do you see for the one who saw you, believed in you, affirmed you, and followed you? What is for him?" He said: "Blessedness (Tuba) is for him." He said: So he wiped his hand and departed. Then the other approached until he took his hand to pledge allegiance to him. He said: "O Messenger of Allah, what do you see for the one who believed in you, affirmed you, and followed you, but did not see you?" He said: "Blessedness is for him, then blessedness is for him, then blessedness is for him." He said: So he wiped his hand and departed.