The words on the underlying blueprint read "Alternate Plan." It refers to God's eternal plan of redemption.The arch contains a waterfall and the separated naked figures of Adam and Eve, which are appropriated figures from Reformation artist Lucas Cranach. After the Fall, mankind is naked and alienated from each other and from God.
The model for the Christ figure is a Jewish friend of mine. His covering robe flows through the waterfall to symbolize the washing of the water of God's Word. A door on the original blueprint reads "major entrance." It intersects the figure's neck. There is a crossbeam behind him and small symbols of communion, a cup and a table that happened to be on the blueprint to mark a table and chair.