While in Prague, the distinguished Renaissance composer Jacobus Handl (Gallus), cultivated contacts at the court of the Emperor Rudolf II, from where he was granted printing privileges, an early form of copyright protection. He composed many charming choral works, which are simply waiting to be discovered. With his motet Duo Seraphim, he succeeded in creating a vigorous paean of praise to the Lord. Even over 420 years after the piece was composed, its powerful echo effects, lively and compelling rhythms, melodic lines that are both cantabile and expressive, and powerfully expressive harmonies create a great impression.