Themes on 'Redemption of the Dead' is not only depicted in historical Christian art but it is also found in ancient Christian writings. 'Baptism for the Dead' is just one aspect of this concept of redeeming the dead that was taught by the Early Christian Church.
Christ's Descent Into Limbo
Ephesians 4:8-10; 1 Peter 3:19
The story of Christ's descent into Hades and his delivering the righteous who were in the bondage of death is told in the Acts of Pilate and the Gospel of Nicodemus, two of the ancient apocryphal texts which throughout the ages have formed part of the spiritual reading of Orthodox Christians. They are not part of the canonized scriptures but are a part of the New Testament Pseudepigrapha.