The Baptismal Cross is a Greek Cross (+) superimposed on an X. The 'X' is not a saltire; rather it is the Greek letter chi, which is the first letter of the Greek word for Christ. (See also Iota-Chi Cross and Chi-Rho Cross.)
This blending of two cross symbols (see also Double Cross) was used in ancient Egypt as a symbol of the Ogdoad, the primeval forces of chaos in Egyptian mythology, represented as eight deities which existed before the creation of the sun god. (See also Taranis.)
Eight symbolises regeneration for many religions. It is the holistic number in Buddhism for the number of steps to end suffering.
This cross is used as a symbol for Neo-Gnosticism and in Catholicism, where the eight arms represent both the age of baptism in the church (eight years), and the eight days between Christ's entry into Jerusalem and his resurrection. The numerical value of the name of Yeshua (Jesus) in Hebrew is 888, making 8 a Christian 'super-number'.
The cross on the left is inlaid into the floor of the narthex at Park Ridge Community Church in Illinois, USA (www.parkridgecommunitychurch.org). It is a beautiful example of an ancient symbol that is perfectly suitable for a modern setting.
Their website explains the Baptismal Cross
...was selected because it calls us to remember two central elements of our faith life. It marks 'our going out and our coming in.'
First, upon entering the sanctuary, we are reminded of our baptism - our welcome into the beloved community by God's grace and through the waters of baptism. The symbol is actually two crosses—and so the eight 'arms' remind us that we come to this place from a wide variety of religious backgrounds and experiences.
When leaving the sanctuary, those same eight 'arms' send us outward to all points of the compass1, to live out our faith in service to God's people wherever we may go.
The Park Ridge Community Church is affiliated to the United Church of Christ, but this cross is not restricted to their use, or indeed by any other Protestant or Catholic church.
Way over on the other side of the world in Orange, NSW, Australia we can see a Baptismal Cross on the grave headstone of an Orthodox Greek Cypriot. (Photo on the right)
The number 8, like the lemniscate symbol for infinity , is a never-ending line. Tracing the shape of the 8 differs from the circle, square, triangle etc. in that the line crosses itself in the centre. This crossing symbolises death. But the line does not stop there; it carries on into a new life, just as the Christian cross symbolises new life.
The eight therefore represents life, death, and rebirth. (A baptismal font is often octagonal for the same reason.)
Eight is symbolic of rebirth or regeneration. This is the meaning of the Baptismal Cross.