Mohammad bin Emad Al-Tostari narrated from Mohammad bin Ahmad bin Edris, from Mohammad bin Abdillah Al-Asbahani, from his father, from Hashim, from Yunus bin Ubaid, from Hasan Al-Basri, from Abdullah, who said:
The MESSENGER OF ALLAH (SWT) said:
On the Day of Judgement, ALI BIN ABI TALEB (ASWS) will sit on FERDOUS, a mountain which has risen higher than Paradise. The Throne of ALLAH (SWT) is on top of this mountain. The rivers of Paradise blast from the sides of this mountain and flow into the gardens of Paradise.
ALI (ASWS) be sitting on a chair made of light and the river of Tasneem will run in front of him. No one will be allowed to cross the bridge without a pass that states ALI’s Wilayat and the Wilayat of his family.
He oversees Paradise so only his lovers will enter it, and he oversees Hell, so only his enemies will enter it.
(Ref : Bihar Volume 27 Page 116 Hadees No.93)