What is the sun rising from the west in Islam?

What the Prophet ﷺ said

The Prophet ﷺ said that the Hour will not be established until the sun rises from the West, and that when people see it, everyone on earth will believe. That is the time when "no good will it do to a soul to believe then, if it believed not before" (Sahih al-Bukhari 4635).

In another hadith, he said this sign is among the first of the great signs that will appear, followed shortly by the beast of the earth, and that whichever comes first, the other follows right after (Sahih Muslim 2941). For the full list of signs, see What are the signs of the Day of Judgement?

What the Quran says

Scholars link this to a verse about the signs of the Lord arriving:

The point is simple. Once the sign appears, the time for free choice and testing is over, so a belief that comes only because of seeing it is no longer accepted.

What happens after the sun rises from the west?

• Repentance is no longer accepted. The Prophet ﷺ said that repentance will not end until the sun rises in the west (Sunan Abi Dawud 2479). Until then the door stays open.
• Faith comes too late for those who delayed. This applies to someone who had not believed or had earned no good through their faith.
• The exact time is unknown. Only Allah knows when this sign will appear.

What should we take from it?

We do not know when this will happen, and there is no need to watch the sky. See When will the Day of Judgement happen?

The lesson is to repent and do good today, rather than putting it off. If you are curious about Islam, you do not need to wait for a sign. See Should I wait for a sign before becoming Muslim?