Sahih al-Bukhari 4305, 4306

Narrated Majashi: I took my brother to the Prophet (ﷺ) after the Conquest (of Mecca) and said, "O Allah's Messenger (ﷺ) ! I have come to you with my brother so that you may take a pledge of allegiance from him for migration." The Prophet (ﷺ) said, The people of migration (i.e. those who migrated to Medina before the Conquest) enjoyed the privileges of migration (i.e. there is no need for migration anymore)." I said to the Prophet, "For what will you take his pledge of allegiance?" The Prophet (ﷺ) said, "I will take his pledge of allegiance for Islam, Belief, and for Jihad (i.e. fighting in Allah's Cause).