In the narration of Baihaqi, it is reported that a Rabbi came to Rasulullah (sallallahu ‘alaihi wasallam) at the time when he was engaged in reciting Surah Yusuf. The Rabbi asked, “O Muhammed! Who imparted the knowledge of this surah to you?” Rasulullah (sallallahu ‘alaihi wasallam) replied, “Allah Ta‘ala imparted the knowledge of this surah to me.”

Hearing this, the Rabbi was extremely astonished. He hastened back to the Jews and said, “Muhammed is reciting the Qur’aan, which is a divine book that seems similar to the Tauraah revealed upon Musa (‘alaihis salaam).”

The Rabbi then brought a group of Jews and came to see Rasulullah (sallallahu ‘alaihi wasallam). The moment they set eyes upon his physical appearance and noted his attributes, they realised that this was the very same Nabi whose appearance the Tauraah had foretold. They also looked at the seal of prophethood which was between the blessed shoulders of Rasulullah (sallallahu ‘alaihi wasallam).

As Rasulullah (sallallahu ‘alaihi wasallam) continued reciting Surah Yusuf, they continued to listen to his recitation attentively, and after listening, they were overcome by amazement and they all embraced Islam.

(Extracted from Seeratul Mustafa 1/412-413)