Ali ibn Abi Talib · The Book on the Description of Hellfire

"The Fire was kindled for one thousand years until it reddened, then it was kindled for one thousand years until it whitened, then it was kindled for one thousand years until it became blackened, so it is dark black."

"Allah will say: 'Remove from the Fire whoever remembered Me one day, or feared Me while in a state of sinning."