Question:
I wonder if the Holy Prophet (S) could read and write before the age of 40? And if it’s true that when Jibraeel (as) said to the Prophet (S) “read”, why didn’t the Prophet (S) answer “I have not learned” or “I cannot read”?

Answer:
Yes, the Prophet did not read or write before the First Revelation. As to whether he could read or write later in his life, there are many different views on that among our scholars. For a correct account of the events of the First Revelation, please see  extracts below from the book ‘The Message’ by Ayatullah Subhani:
    “…an angel placed a tablet by his side and said: ‘Recite’. And the Prophet on account of the fact that he was unlettered and had not learned to read and write, replied that he was unable to read. The Archangel Jibreel pressed him severely and then asked him to recite. However, he repeated the same reply. The angel again pressed him severely. This action was repeated thrice and after the third pressure he suddenly felt within himself that he could read the writing on the tablet held by the angel. He then read the following verses which are infact reckoned to be the introduction of the Book of human welfare:
    “Recite in the name of your Lord who created (all things). He created man from a clot of blood! Recite, your Lord is the Most Bountiful One, Who by the pen taught man what he did not know. (Surah al-Alaq, 96 1- 5 )
Archangel Jibreel accomplished his assignment and after the revelation the Prophet also descended the mountain of Hira and proceeded towards Khadijah’s house. The above verses clearly indicate the programme of the Holy Prophet in a nutshell, and tell in obvious terms that the foundation of his religion is provided by recitation and reading, learning and wisdom and use of pen.
The great soul of the Holy Prophet was illumined with the light of revelation. He recorded in his heart what he had heard from the angel (Jibreel). After this incident the same angel addressed him saying:
“O Muhammad! You are the Messenger of Allah and I am Jibreel”
When he entered the house his dear wife observed signs of deep reflection and anxiety in his face and asked him what the matter was. The Holy Prophet related to Khadijah what had happened and also added the sentence ‘I felt afraid of myself’. Khadijah looked at him with respect, prayed for him and comforted him by mentioning some of his good qualities. Amongst other things she said: ‘You are kind to your kinsfolk, show hospitality to your guests and you are not afraid of bearing hardships in the right path. Allah will assist you’.”
Answered by: Dr Ali Alsamail