Abu Sa'eed Al-Khudri narrated that about: Kal Muhl, the Prophet (s.a.w) said: "Like boiling oil, such that whenever it is brought near him the skin of his face falls into it." And also with this chain, from the is Prophet SAW, that he said: "If a bucket of Ghassaq were poured out in the world, the people of the world would rot. (Da'if) And the meaning of his statement: "The Kithaf of each wall" is its thickness.

It is narrated from Abu Sa'id Khudri, may Allah be pleased with him, with the same chain, that the Prophet, peace and blessings be upon him, said: "Hell is surrounded by four walls, and the thickness of each wall is like the distance of forty years."

Abu Sa'id Khudri (may Allah be pleased with him) narrated with this same chain that the Prophet (peace and blessings of Allah be upon him) said: "If a bucket of «غساق» (the material of the people of Hell) were to be poured out in the world, the people of the world would rot." Imam Tirmidhi says:
1- We know this hadith only from the narration of Rushdin bin Sa'd, and people have spoken about Rushdin; they have spoken about his memory,
2- The meaning of the saying of the Messenger of Allah (peace and blessings of Allah be upon him) «كثف كل جدار» is the thickness of every wall.