It is unanimously accepted that the first five verses of the chapter Al-‘Alaq (The Clot) were the first words of revelation to the Holy Prophet Muhammad (sas). The remaining verses of the chapter were revealed later on. The Holy Prophet was deeply engrossed in devotion (meditation) in the Cave of Hira when the Angel Gabriel descended and said to him, “Read!”
He replied, “I cannot read.”
The Angel then squeezed him in a tight embrace and repeated the command: “Read!” Again the Holy Prophet answered: “I do not know how to read.”
This happened three times. Then the Holy Prophet began to read and the Angel read out these five verses to him. The Holy Prophet then returned home, and so overcome was he by the majesty of the revelation, that the flesh on his shoulders and throat began to shiver so that he requested of Lady Khadija, “Cover me. Cover me.”