When Muhammad was forty years old he retreated for meditation to a cave on Mount Hira and on the seventeenth day of the fasting period called Ramadan, he was overpowered by the presence of divinity as represented by the angel Jibril (Gabriel). The angel taught Muhammad the proper prayer rituals, recognized him as Allah’s Messenger (rasul) and commanded him to “say” (iqra), the words of Allah which would be the holy book of Islam, the Qur’an. The Prophet would receive segments over the next twenty-three years.