There is the cryptic article of the Apostles Creed: "He descended into hell."
There are the enigmatic and controverted verses of Scripture: "For Christ also suffered for sins once, the righteous for the unrighteous, that he might lead you to God. Put to death in the flesh, he was brought to life in the spirit. In it he also went to preach to the spirits in prison, who had once been disobedient while God patiently waited in the days of Noah during the building of the ark, in which a few persons, eight in all, were saved through water" (1 Peter 3:18–20).