Perhaps he had made a preview visit to paradise, as hinted by his words to one of the men crucified with him. The First Letter of Peter hit on the idea that Jesus preached to "the spirits in prison", in the realm of the dead. Logic suggested that if he preached to them, they must have had a chance of repentance - unless the preaching was another punishment, a 38-hour sermon! It assumed a sort of Last Chance Saloon, where spirits coping with the reality of death could choose for God or not. Out of this developed the idea of purgatory.
Others thought that Jesus' descent meant that those who had died in a state of grace before Jesus' own death could now be set free from their "limbo" and enter heaven. Two of the main Christian creeds, the Apostles' and the Athanasian, taught that Jesus "descended into hell", probably meaning he was really and truly dead. hat might officially settle the matter, except that the Descent got into bad company, appearing in very dodgy creeds and gospels such as the Blasphemy of Sirmium (359CE) and the Gospel of Nicodemus.
Just to confuse matters more, what was meant by "hell" began to change its meaning from the place of the dead to the place of the damned. From about 1000CE, the story circulated that Jesus nipped down to hell and harrowed it - harrow from the Middle English harwe, "to cause distress to". In other words, he went and created havoc in the Devil's own dominion, leaving in time to be back in Jerusalem for Sunday morning. The harrowing of hell became a favourite theme for medieval art and mystery plays. In 2000CE we take a rather flippant view of all these matters, reducing Serra's demons in the picture to cartoon devils with horns, forks and long tails and "Frying tonight" notices, without any thought of real suffering.
We should not neuter hell like that. Many 20th-century people have descended into hell: victims of child abuse, of Auschwitz, of war, of slow starvation on a rich planet. Fewer have come back.
Terence Copley is professor of religious education at the University of Exeter