In an underground basement Carl imprisons his female victims in a glass tank that slowly fills with water. In the Hebrew Scriptures, circumcision happens on the 8th day. In Christian Scriptures, circumcision corresponds to baptism. Biblically, the number 8 is the number of new beginnings, new birth, new creation. When Carl was a boy he was baptized in a river by his church.
Baptism is an act that symbolizes death and resurrection.
Going down into the water is a reenactment of the death of Jesus Christ and coming up out of the water signifies his resurrection. The baptismal water is both a symbol of the grave and re-birthing. He came to believe that baptizing his victim with a baptism devoid of a resurrection would set them free. He had baptism turned upside down. Following the death of his victims, he would drain the water from the tank, remove the victim's body and bleach it powder white -a symbol of purity and sinlessness.