"And I say also unto thee, That thou art Peter, and upon this rock I will build my church; and the gates of hell shall not prevail against it." (Matthew 16:18)

The castle built on the cliff is the symbol of the Christian Church. It is a typical motif, also appears on Veit Stoss' High Altar of St. Mary in Cracow, in the background of the Nativity and The Entombment.