The doctrine of hell as a cosmic torture chamber was propounded by a number of prominent medieval thinkers, among them Augustine and Aquinas.
According to Kelly James Clark, in God is Great, God is Good: Medieval Conceptions of Divine Goodness and the Problem of Hell,
“Augustine contends that the tortures of the damned are both physical and spiritual and that the damned, though consumed by physical fire, are kept in existence by God himself. Aquinas rejects the notion that the damned are tormented solely by fire, arguing that a variety of tortures will be employed. The term ‘fire’ is prevalent in scripture to describe the intensity of the pain, not the specificity of the torture. Eternal suffering, likened to the horror of being burned, is inflicted by torment ‘in many ways and from many sources’ and without respite. Indeed, hell will be so arranged ‘as to be adapted to the utmost unhappiness of the damned,’ and there will be, he argues, just enough light to perceive ‘those things which are capable of tormenting the soul.’ (Summa Theologica Suppl. Q. 97, Art. 5) One will, for example, see the corporeal fires and smell their stench as they burn one’s corporeal body. This never ending fire, Aquinas believes, is sustained not by fuel but by the very breath of God.”
“The medieval notions of goodness and hell, seem to make God more a sadistic torturer who keeps her victims alive just so she can maximally inflict pain than a caring parent who would with all her power never cease attempting to benefit her child through her sufferings.”