ASHABU ‘L-KAHF الشاب الكهف.
“The Companions of the Cave,” i.e. the Seven Sleepers, mentioned in the Suratu ‘l-kahf, or Chapter xviii of the Qur’an. The story, as told by early Christian writers, is given by Gibbon (Rise and Fall, Chapter xxxi.). When the Emperor Decius persecuted the Christians, seven noble youths of Ephesus are said to have concealed themselves in a cave in the side of a mountain, where they were doomed to perish by the tyrant, who gave orders that the entrance should be firmly secured with a pile of huge stones. They immediately fell into a deep slumber, which was miraculously. prolonged, without injuring the powers of life, during a period of 187 years. This popular tale, which Muhammad must have heard when he drove his camels to the fairs of Syria, is introduced into the Qur’an as a divine revelation.
Based on Hughes, Dictionary of Islam