Amali Tusi: Abu Muhammad Fahham said: Narrated to me Abu TayyibAhmad bin Muhammad bin Batta that he never entered the shrine; he performed theZiyarat from the window. He says:
“Once on the day of Ashura at noon when the sun was at its peak and the roads were deserted, I came out to perform the Ziyarat of Imam Hasan Askari (a.s.) at his shrine. But I dreaded the tyrants and oppressors of the town. ThusI came to the surrounding wall that led into the orchard. When I looked fromthere, I saw a man sitting at the door with his back to me. And as if he waslooking at something in his notebook. Then he addressed me: O Abu Tayyab,where are you going?
His voice was very similar to that of Husain bin Ali bin Abu Ja’far binReza. I said to myself that perhaps it was Husain who had come for theZiyarat of his brother. So I said: My chief, I am going to do the Ziyarat fromthe window. When I come back I will fulfill your rights also.
He said: Why from the window? Why not from inside?
I replied: There is an owner of this house and I cannot enter without hispermission.
He said: You are our true devotee and follower. Would we disallow youto enter our place? Go in and perform the Ziyarat.
So I came upto the door and found no one there. I was worried and called for the sentry who opened the door for me and I entered.
Then we used to tell Abu Tayyab: You never used to go in. You did the Ziyarat from outside only?
He said: The owner of the house had given permission to me and youpeople remain.”
Reference : Beharul anwar vol 51.52.53 , Part 1 , The Promised Mahdi