Christian Lange on the Islamic vision of hell

Am reading right now parts of a recently-published volume called Public Violence in Islamic Societies (2009 Edinburgh University Press) and one of the articles in it, 'State Punishment and Eschatology' by Christian Lange, has some great clarifications regarding the medieval Islamic understanding of hell:

In the eschatological imaginaire of medieval Islam, punishment of Muslims in the other world is thus conceived of as a real threat. There is a tangible fear of becoming the target of divine acts of violence after death. This is not an ever-present fear, perhaps, but rather, a nagging suspicion that things might go terribly wrong after all. (p 160).

It is interesting to note that, despite their ugliness and general nastiness, the gaolers of hell are angels. They are, as it were, on the side of power. In a sense, they are agents of God's siyasa, His terrifying but ultimately just use of punishment. (p 163)