The Apostles Creed : I [We] believe in God, the Father almighty, creator of heaven and earth. I [We] believe in Jesus Christ, his only Son, our Lord. He was conceived by the power of the Holy Spirit and born of the Virgin Mary. He suffered under Pontius Pilate, was crucified, died, and was buried. He descended to the dead. On the third day he rose again. He ascended into heaven, and is seated at the right hand of the Father. He will come again to judge the living and the dead. I [We] believe in the Holy Spirit, the holy Catholic Church, the communion of saints, the forgiveness of sins, the resurrection of the body, and the life everlasting. Amen. (Note: The part that reads, “I believe in . . . the holy catholic church” does not refer to the Roman Catholic Church.)
When the saints of the Old Testament died, Jesus had not yet suffered and died. There was no covering for their sin other than the sacrifice of animals offered. So they were in that part of Hades/Hell called Abraham’s Bosom, being comforted as they awaited the arrival of the Messiah who would break through the doors of hell and free them from their prison — awaiting the true sacrifice that would set them free from sin for ever and ever.
Revelation 1:18 “I am he that liveth, and was dead; and, behold, I am alive for evermore, Amen; and have the keys of hell and of death.”
Isaiah 61:1, “The Spirit of the Lord GOD is upon me; because the LORD hath anointed me to preach good tidings unto the meek; he hath sent me to bind up the brokenhearted, to proclaim liberty to the captives, and the opening of the prison to them that are bound;” Luke 4:18, “The Spirit of the Lord is upon me, because he hath anointed me to preach the gospel to the poor; he hath sent me to heal the brokenhearted, to preach deliverance to the captives, and recovering of sight to the blind, to set at liberty them that are bruised,”
Psalms 68:18, “Thou hast ascended on high, thou hast led captivity captive: thou hast received gifts for men; yea, for the rebellious also, that the LORD God might dwell among them.” Ephesians 4:8-10, “Wherefore he saith, When he ascended up on high, he led captivity captive, and gave gifts unto men. (Now that he ascended, what is it but that he also descended first into the lower parts of the earth? He that descended is the same also that ascended up far above all heavens, that he might fill all things.)”
What did Peter say about what Jesus did when he descended into Hell? 1 Peter Chapter 3:18-19, “For Christ also hath once suffered for sins, the just for the unjust, that he might bring us to God, being put to death in the flesh, but quickened by the Spirit: By which also he went and preached unto the spirits in prison;”