Is the story of the Children of Israel asking Moses (peace be upon him), "Does your Lord sleep?" and Moses's spending the night with two glass bottles, which then broke, the true reason behind the revelation of Ayat al-Kursi? And is it possible for the reason for the revelation of a verse to have occurred before the prophethood of Prophet Muhammad (peace be upon him)?

This story is from the accounts of the Children of Israel and it is not permissible to attribute it to the Prophet (peace and blessings of Allaah be upon him). It contains things that are unfitting for Musa (peace be upon him). The fact that Ibn Katheer and other commentators mentioned it does not mean it is authentic, for they may criticize it or mention it with its chains of narration so that the reader can verify it.