Fighting for the Cause of Allah (Jihaad)
حَدَّثَنَا إِبْرَاهِيمُ بْنُ مُوسَى، أَخْبَرَنَا يَزِيدُ بْنُ زُرَيْعٍ، عَنْ خَالِدٍ، عَنْ أَبِي عُثْمَانَ النَّهْدِيِّ، عَنْ مُجَاشِعِ بْنِ مَسْعُودٍ، قَالَ جَاءَ مُجَاشِعٌ بِأَخِيهِ مُجَالِدِ بْنِ مَسْعُودٍ إِلَى النَّبِيِّ صلى الله عليه وسلم فَقَالَ هَذَا مُجَالِدٌ يُبَايِعُكَ عَلَى الْهِجْرَةِ. فَقَالَ " لاَ هِجْرَةَ بَعْدَ فَتْحِ مَكَّةَ، وَلَكِنْ أُبَايِعُهُ عَلَى الإِسْلاَمِ ".Narrated Abu `Uthman An-Nahdi:Mujashi (bin Mas`ud) took his brother Mujalid bin Mas`ud to the Prophet (ﷺ) and said, "This is Mujalid and he will give a pledge of allegiance to you for migration." The Prophet (ﷺ) said, "There is no migration after the Conquest of Mecca, but I will take his pledge of allegiance for Islam
From Sahih al-Bukhari, whose reports the scholars accept as authentic.