question #1 Sahih Muslim Introduction 46, Introduction, Narration 45 : How long did it take for Alqamah to memorize the Qur’an?

‘I memorized the Qur’ān in two years’. Al-Hārith said: ‘The Qur’ān is easy; the revelation [i.e. the secret revelation to Alī in the belief of the Shī’ah] is more difficult ’.