Imam Hassan (AS) used to recite the holy Quran with beautiful voice, and his knowledge of the Quran was complete in his childhood. Imam Hassan (AS) used to recite Surah Al-Kahf before sleeping at night. It is narrated that when the Prophet of Islam (PBUH) was alive, a person entered the Mosque and asked a man about the witness and what is to be witnessed [1]. The first man answered: The witness is Friday and the Day of Arafah is the subject of the witness. The same question was asked from the second man, but he replied: The witness is Friday and the subject of the witness is the Eid-ul-Adha.
That questioner went to a child who was sitting in a corner in the Mosque, and the child answered: “The witness is the Prophet Mohammad (PBUH) and the subject of the witness is the Day of Judgment; have you not heard what God said about the Prophet (PBUH): O’ Prophet, truly God sent you as a Witness, a Bearer of glad tidings, and a Warner [2]; and about the Day of Judgment, God said: That is the day when mankind will be gathered together [3].” The narrator added: I asked who was the first person who answered the question? They replied: Ibn Abbas. Then asked about the second man who replied, and they said: Ibn Omar, and then asked about that child who answered better than all and correctly, they replied: He is Hassan Ibn Ali ibn Abitaleb (AS) [4].
[1] Ayah 3, Surah Al-Brooj.
[2] Ayah 45, Surah Al-Ahzab.
[3] Ayah 103, Surah Al-Hud.
[4] Beharul Anwaar, Vol. 43, page 345.
source : en.shafaqna.com