The church is built on a ground plan of a five-pointed star. It is based on a legend when a crown of five stars appeared above the dead body of the drowned St John of Nepomuk. The symbol appears repeatedly in many elements of the building.
The church has five entrances, five chapels and five altars. Also the Latin word TACUI – I was silent – contains five letters. This is a reminder of the legend according to which St John of Nepomuk paid with his life for not revealing the confessional secret of the Queen Sophia. And there are many more Christian symbols characterized by the number five...
The dominant feature of the church dome is a large red tongue, an attribute of the silence of St John of Nepomuk, surrounded by a circle of flames and shining rays. However, this decoration is a result of a change in the original project, which initially contained a central ten-pointed star. The change reflected the fact that a rare relic, the lingula of St John of Nepomuk (a bone to which a tongue is attached), was acquired for this newly built church and the architect used this fact to strengthen the significance of the tabernacle as a reliquary. The depicted tongue is intended to be a symbol of the victorious weapon – the tongue as the sword of the martyr John. That is why some windows have the shape of a tongue as well, specifically those in the chapels above the entrances. Other windows are built in the shape of a bishop's mitre, referring to the right of the local abbots to wear the mitre on ceremonial occasions. The last shape used for the windows is a spherical equilateral triangle, symbolizing the Holy Trinity.
