Sayyiduna Mujashi' bin Mas'ud al-Sulami (may Allah be pleased with him) says: I brought my brother Sayyiduna Abu Ma'bad (may Allah be pleased with him) to the Messenger of Allah (peace and blessings be upon him) after the conquest of Makkah and said: "O Messenger of Allah! Take his pledge of allegiance on emigration." He (peace and blessings be upon him) said: "Those who had to emigrate have done so (and now there is no emigration)." I said: "O Messenger of Allah! Then on what will you take his pledge?" He (peace and blessings be upon him) said: "On Islam, jihad and goodness." Then he (peace and blessings be upon him) took his pledge. Abu Uthman (may Allah have mercy on him) says: I met Sayyiduna Abu Ma'bad (may Allah be pleased with him) and told him what Sayyiduna Mujashi' (may Allah be pleased with him) had said, and he said: Mujashi' spoke the truth.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب السير / 17768