Why will people on the Day of Judgment go to all the prophets – starting with Adam and ending with Prophet Muhammad, peace be upon him – to ask for intercession, despite their knowledge that Prophet Muhammad is the intercessor? And does this sequence apply to those who were unaware of this?

The Day of Judgment is a momentous day when people will be stunned by everything and will not recall any prior knowledge due to the horrors. Perhaps Allah will make them forget this to demonstrate the Prophet's superiority, as happened on the day of the Prophet's passing, when people were stunned until Abu Bakr reminded them with Allah’s words: "And Muhammad is not but a messenger. [Other] messengers have certainly passed on before him."

Not all Muslims are aware of the lengthy Hadith of Intercession narrated by Abu Hurairah, where people seek intercession from the prophets successively, and each prophet says, "Myself, myself, myself," until they reach Muhammad (peace be upon him).

This intercession is for the commencement of the reckoning. One should not preoccupy themselves with unseen details except those for which an authentic text has been revealed.