How can one reconcile Islam's prohibition of shed blood with Ibn Az-Zubair's act of drinking the Prophet's—may Allah's peace and blessings be upon him—cupping blood, and the Prophet's saying to him: "By Allah, the Fire shall not touch your body"?

The story of Ibn Al-Zubayr drinking the Prophet's blood is authentic. The permissibility of drinking his blood is specific to him, due to his unique status, peace and blessings be upon him. Zakariya Al-Ansari mentioned that among his unique characteristics is that his blood and urine provide healing. It was also said that Ibn Al-Zubayr drank the blood without the Prophet's knowledge. This is supported by the Prophet's question to Abu Hind the cupper: "Woe to you, O Salim! Did you not know that blood is unlawful? Do not repeat it."