Harrowing of Hell

The Harrowing of Hell is a doctrine in Christian theology referenced in the Apostles' Creed and the Athanasian Creed (Quicumque vult), which states that Jesus "descended into Hell". It has been termed the most controversial phrase in the Apostle's Creed.
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[Folklore] The medieval fable of Christ's vanquishing of Hell during the time between his crucifixion and resurrection. The story first appears in the apocryphal Gospel of Nicodemus, also known as the Acts of Pilate, written by a Roman praetorian named Ananias in probably 425 CE. It is subsequently repeated in Aelfric's homilies c. 1000 CE --which is the first known inclusion of the world "harrowing". The story is widespread in medieval English literature. Presumably the story is somewhat included in the canon of the Church, as it is found in the Catholic Encyclopedia. However, it appears mainly as European folklore.