Sayyiduna Abdullah bin Amr bin al-As (may Allah be pleased with them both) narrates that the Messenger of Allah (peace and blessings be upon him) said: "If indeed a stone like this"—and he (peace be upon him) pointed towards his skull—"is thrown from the sky towards the earth, and that is a distance of five hundred years, then surely it would reach before nightfall. And if indeed it is let go from the end of that chain, then surely it would keep falling for forty years, day and night, before reaching (the bottom of Hell)."