In some cultures and sects, Azrael, also pronounced as Azrail/Azriel, is the name referring to the angel of death by some Arabic speakers. The name is mentioned in a few Muslim books but is argued by some Muslims as having no basis of reference. Along with Gabriel, Michael, Raphael and other angels, the Angel of Death is believed by Muslims to be one of the archangels. The Qur'an states that the angel of death takes the soul of every person and returns it to God. However, the Qur'an makes it clear that only God knows when and where each person will be taken by death, thus making it clear that the Angel of Death has no power of his own. Several Muslim traditions recount meetings between the Angel of Death and the prophets. The most famous being a conversation between the Angel of Death and Moses. He watches over the dying, separates the soul from the body, and receives the spirits of the dead in Muslim belief. Rather than merely representing death personified, the Angel of Death is usually described in Islamic sources as subordinate to the will of God "with the most profound reverence." However, there is no reference within the Quran or any Islamic teachings giving the angel of death the name of Azrael.
A man who was once Jewish and later converted to Islam, Kaab al Ahbar who was described as a companion of the Caliph Omar and was considered to be one of the oldest authorities for Jewish traditions among the Muslims of his time. He was recorded as the man who named the angel of death in Islam as Azrael, as well as his description. However, this has been challenged and disputed by some scholars, particularly Shia Muslims. The office of the Grand Ayatollah, Ali al Sistani of Iraq said in a letter that Kaab was "a liar and a hypocrite" and accused him of placing many Jewish superstitions in Islamic prophetic texts.
Some Sunni Muslim scholars, while having no negative view of Kaab, doubt the authenticity of the tradition itself. Shaykh al-Albaani and Shaykh Ibn 'Uthaymeen have both also disputed the usage of the name Azrael as it's not used in the Qur'an itself. However, the same can be said about many Prophets and Angels, many of whom aren't mentioned by name in the Qur'an.
(from Wikipedia)
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