The "necessity" of a hell

"Hell sensibly extends moral responsibility into the next world. I say 'sensibly' because this is the only way to prevent eschatology from making a mockery of the present world. I do not know what befell Mother Teresa of Calcutta when she died, nor what has become of Joseph Stalin. But the same thing cannot have come upon them both. If there is any moral rhyme or reason in the Universe, all human beings cannot be equally well off as soon as they breathe their last and wake again. The next life continues this life; it does not start at square one. … Hell which outrages our moral sensibilities, is paradoxically a product of those same sensibilities. It is a postulate of the conscience. It calls for divine justice to make things right, and it solemnly expresses the profound significance of our moral and religious decisions, a significance that crosses even the cordon of death, and goes so far that it raises the possibility of an ongoing alienation from God. In these particulars, hell makes good sense." Dale C. Allison, 2005, 'The Problem of Gehenna', p.99 in Resurrecting Jesus, t&t clark.