Today is the birthday of Willem-Alexander, king of the Netherlands. Everywhere in our country we sing our national anthem, Het Wilhelmus. Originally this is a song of propaganda for William the Silent, prince of Orange, our present king's forefather.
Jan Zwart's fantasy is in march tempo, but halfway quiets down to a prayer for God's blessing for the king or queen. For this, Zwart uses the Genevan melody for Psalm 134, also known from the Lutheran hymn Herr Gott, dich loben alle wir.
Maybe we could say, this is some kind of Dutch version of God save the King...