Ali Bin Ahmad narrated to us...
Ali Bin Ahmad narrated to us, from Muhammad Bin Abu Abdullah, from Muhammad Bin Ismail, from Ali Bin Al Abbas, from Umar Bin Abdul Aziz, from Hisham Bin Al Hakam who said, ‘I said to Abu Abdullah -asws (Imam Jafar Sadiq -asws ), ‘Inform me about what the Prostrations (Sajud) are allowed upon, and about what it is not allowed?’ He -asws said: ‘The Prostrations are not allowed except upon the earth or upon what the earth grows on, excluding what is eaten or worn (originating from the earth)’.
So, I said to him -asws , ‘May I be sacrificed for you -asws ! What is the reason with regards to that?’ He -asws said: ‘Because the Prostration, it is the humbleness to Allah -azwj Mighty and Majestic, so it is not befitting that it should happen upon what is eaten or worn, because the sons of the world are enslaved to what they are eating and they are wearing, and (when) the prostrator in his Prostration, (he) is in the worship of Allah -azwj the High, therefore it is not befitting that he should place his forehead during his Prostration upon a thing which the sons of the world are enslaved to, and have been deceived by its deception.
And the Prostration upon the earth is the most preferable, because it reaches in the reverence and the humbleness to Allah -azwj Mighty and Majestic’.
My father narrated, from Muhammad Bin Yahya, from Muhammad Bin Ahmad, from Al-Sayari who said, ‘One of the people of Al-Madain wrote to Abu Al-Hassan -asws asking him -asws about the Prayer upon the glass. He said, ‘So when I had written my letter to him -asws , so I thought to myself, ‘It is from what the earth grows, and it was not for me that I should be asking him -asws about it’.
He said, ‘So he -asws wrote back: ‘Do not Pray upon the glass, for you have discussed it within yourself that it is from the growth of the earth.