For in the Market-place, one Dusk of Day,
I watch'd the Potter thumping his wet Clay:
And with its all obliterated Tongue
It murmur'd--"Gently, Brother, gently, pray!"
This is the thirty-sixth quatrain of the FitzGerald's Rubaiyat. The use of clay and pottery has been a recurring theme in the last two quatrains as well. In previous quatrains the earthen pot has told the bearer that life is short and so make full use of it and ultimately all will be dust and from this new life will emerge living and dreaming the same thoughts. In this quatrain the meaning is lot more obscure.
In the market place, in a dusk of the any ordinary day, I watched the maker, the potter thumping and shaping his wet clay. He giving form to his creation, he molding the clay and giving it birth. But the earthen clay with its obliterated mouth, a speech that is hardly audible says, gently my brother, gently! In a slow murmur, the clay says to the potter to create his creation gently. Unlike the notion of creator where he has absolute control and its creation, in this quatrain the relationship between the clay and potter seem more humble and private (sibling-like).
One possible explanation could be that maybe the creation and the creator is not different. Instead they are one and the same. There is no separate realms of higher and lower beings, no separate sphere of creator and the creation. Everything existing is in the midst of the creator. And in this divine soup, the earthen clay seeks out to the supernal potter and supernal potter seeks out to the earthen clay making them whole again.
