It is narrated from Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) concerning the saying of Allah Almighty, "And those with whom your right hands have made a pledge, give them their share" [Surah Al-Nisa': 33] , that he said: "When the Muhajirun came to Madinah, on the basis of the brotherhood which the Messenger of Allah (peace and blessings be upon him) had established between them and the Ansar, the Muhajirun would inherit from the Ansar (upon death) instead of their close relatives. Then when this verse was revealed, 'And for each We have appointed heirs of what is left by parents and close relatives,' it abrogated the former arrangement; and (the saying of Allah Almighty) 'And those with whom your right hands have made a pledge, give them their share' now refers (not to inheritance but) to a share of help and sincere goodwill." This hadith is sahih (authentic) on the condition of the two Shaykhs (Bukhari and Muslim).