Al-Muwaffaq and others relate the agreement of the entire Muslim community that agency is, in principle, permissible, and the need for it is pressing, for no one can personally attend to everything he requires.

Formation of an agency contract:
An agency is concluded by any utterance that conveys authorization, such as: “Do such-and-such,” or, “I permit you to do such-and-such.”

Acceptance may take place immediately or after a delay, by any word or deed that indicates acceptance, because the acceptance of the Prophet’s agents—peace and blessings be upon him—occurred after he had commissioned them.

Agency may be limited to a set period or suspended on a condition, as when one says, “You are my agent for one month,” or, “Once the registration of my house is completed, sell it.”

The agent must be specifically identified; therefore, saying, “I have appointed one of these two as my agent,” or appointing someone whose identity is unknown, does not establish agency.

Matters in which agency is valid:
Agency is valid in every matter concerning human rights that allows representation, whether in concluding contracts or in dissolving them. Contracts include sale, purchase, lease, loan, and muḍāraba (profit-sharing partnership); dissolutions include divorce, khulʿ, manumission, and mutual rescission. Agency is likewise valid in every act of worship involving the rights of Allah that admits representation;