Before entering the Vestibule of hell, Dante and Virgil must pass through the gate of hell, and inscribed in stone above the gate is the following:
“I am the way into the city of woe,
I am the way into eternal pain,
I am the way to go among the lost.
Justice caused my high architect to move,
Divine omnipotence created me,
The highest wisdom, and the primal love.
Before me there were no created things
But those that last forever—as do I.
Abandon all hope you who enter here.”
In “Devaduta Sutta”, the 130th discourse of the Majjhima Nikaya, Buddha teaches about hell in vivid detail. Buddhism teaches that there are five (sometimes six) realms of rebirth, which can then be further subdivided into degrees of agony or pleasure. Of these realms, the hell realms, or Naraka, is the lowest realm of rebirth. Of the hell realms, the worst is Avīci or “endless suffering”. The Buddha’s disciple, Devadatta, who tried to kill the Buddha on three occasions, as well as create a schism in the monastic order, is said to have been reborn in the Avici Hell.
Like all realms of rebirth in Buddhism, rebirth in the Hell realms is not permanent, though suffering can persist for eons before being reborn again. In the Lotus Sutra, the Buddha teaches that eventually even Devadatta will become a Pratyekabuddha himself, emphasizing the temporary nature of the Hell realms. Thus, Buddhism teaches to escape the endless migration of rebirths (both positive and negative) through the attainment of Nirvana.
The Bodhisattva Ksitigarbha, according to the Ksitigarbha Sutra, made a great vow as a young girl to not reach Nirvana until all beings were liberated from the Hell Realms or other unwholesome rebirths. In popular literature, Ksitigarbha travels to the Hell realms to teach and relieve beings of their suffering.
And since a place is assigned to souls in keeping with their reward or punishment, as soon as the soul is set free from the body it is either plunged into hell or soars to heaven, unless it be held back by some debt, for which its flight must needs be delayed until the soul is first of all cleansed.
— St Thomas Aquinas