Sahih Muslim Book 20, Hadith Number 4600.

Chapter : No migration after the conquest of Mecca but allegiance could be sworn (to a rightful leader) on serving the cause of Islam, on fighting in the way of Allah and on following the path of virtue.

It has been narrated on the authority of Abu Sa’id al-Khudari that a Bedouin asked the Messenger of Allah (may peace be upon him) about Migration. He replied: Do you talk of Hijra? The affair of Hijra is very difficult. But have you got camels? The bedouin said: Yes. He asked: Do you pay the poor-rate payable on their account? He replied: Yes. He (the Holy Prophet) said: Go on doing good deeds (across the seas), for surely God will not leave any of your deeds un-rewarded.