I got this message recently by Messenger:
Good morning Bishop! I have a question. Why do we say, He descended into hell in the apostles creed. This is brought up because my aunt of 98 had the Last Rights yesterday.
Here was my response:
Good question Joe. I am sorry to hear of your aunt being in distress.
The short answer is that, prior to the death of Christ, all souls entered the same state, known in Hebrew as Sheol. It is described as a place of darkness and shadow, not the fullness of life and light that characterizes the presence of God.
The hell that is described in the creed is not the hell of the damned, but Sheol. If there had not been a positive act by God it would have been a true hell of eternal separation from God, but of course God did act for their salvation.
That act was Christ's descent into Sheol. In his human soul, he entered the state of Sheol as with any other human soul. However, as he is also a divine person, he effectively brought the presence of Heaven with him into Sheol, forever transforming it.
Sheol, therefore, no longer exists as the universal default state.
Christ descended into hell (Sheol) but has transformed Sheol by descending into it.
Hope that helps.