What is the meaning and details of al-mu'akha (brotherhood), how were those who were to be bound in brotherhood chosen, do those bound in brotherhood inherit from each other according to Sharia, are the wives (female relatives) of the person one is bound in brotherhood with, such as daughters or sisters, forbidden to one, was Hamza's daughter forbidden to Zayd ibn Harithah due to the Prophet having bound him and Hamza in brotherhood, what is the wisdom behind al-mu'akha, and who were those not bound in brotherhood?

When the Prophet, peace and blessings be upon him, emigrated to Medina, he established a bond of brotherhood between the Muhajirun (emigrants) and the Ansar (helpers) to address the financial crisis of the Muhajirun and strengthen their relationships. This brotherhood was established in the house of Anas ibn Malik or in the mosque, and it included ninety or one hundred men. The Muhajir would inherit from the Ansari by virtue of this brotherhood, but this ruling was abrogated by the verses of inheritance, and the brotherhood remained in mutual support and assistance. The Prophet established brotherhood among his companions twice: the first was among the Muhajirun themselves before the Hijra, and the second was between the Muhajirun and the Ansar after the Hijra to Medina, with the aim of removing the desolation of estrangement and strengthening unity. The Quran and Sunnah emphasized the importance of this brotherhood, and mentioned the rights of a Muslim upon another Muslim, such as greeting, visiting the sick, and offering counsel, with additional rights for kinship. The pious predecessors considered brotherhood for the sake of Allah to be among the greatest blessings with which Allah united the hearts of the believers.