Nothing but a quote and screenshot from shia site.
Alshaikh Alsadouq states in Oyoun Akhbar Al-Rida (pbuh) that Solaiman Bin Hafs Almerwazy said:” I heard Abu Al-Hasan Mousa Bin Jaafar (pbuh) say:” Whoever visits the grave of my son Ali, will have seventy accepted pilgrimages.” I said:” seventy pilgrimages?!” He said:” Indeed! He will have seventy thousand pilgrimages.” Then he said:” A pilgrimage may not be accepted, but whoever visits him or sleeps over night at his grave, will be as if he visited Allah in His throne.“ I said:” As visiting Allah in His throne?!” He said:” yes! At Resurrection Day, there will be four of the first time and four of the last on Allah’s throne. As for the four of the first, they are Nouh, Ibrahim, Mousa and Issa (Allah’s peace be upon them). As for the other four, they are Mohammad, Ali, Al-Hasan and Al-Hossein (Allah’s praises and blessings be upon them). Then, the visitors of the Imams’ graves will sit with us. Indeed! The ones with the highest rank and the nearest to us are the visitors of the grave my son Ali (pbuh).”
 Oyoun Akhbar Al-Rida vol.1 p.290, Amali Al-Sadouq p.182, Al-Bihar vol.99 p.35, Al-Kafi vol.4 p.585, Kamil Al-Ziarat p.511, Jawaher Al_kalam vol.20 p.98, Rawdat Al-Wa’izeen p.234, Wasa’el Al-Shia vol.10 p.442