Another explanation of Araaf is that it is a wall, which will be erected between people of paradise and people of hell on Sirat as mentioned in Surah Al Hadid. The Lord of the Universe says: (0 My Dear Messenger!) On that Day, you will see the Faithful in such a condition that their radiance will enlighten their front and their side. (A voice will be heard): Good tidings to you for you will get the eternal paradise beneath which rivers flow. It is indeed a great success of yours.
On that Day, the hypocrites will tell the Faithful: Just look at us also! We too may benefit from your radiance. They will be told: Return to the world and find out some other light. Then a wall will be raised between the said two groups. There will be a door in that wall. On one side of it will be only Mercy (for the Faithful) and on the other only punishment (for the unbelievers and hypocrites).
Then separation would be brought about between them, with a wall having a door in it; (as for) the inside of it, there shall be mercy in it, and (as for) the outside of it, before it there shall be punishment. (57:13)
