 In Brussels, Dering took up the position of organist to a community of English Benedictine nuns at the Convent of Our Lady of the Assumption.There, he published his collections of Latin motets, "Cantiones Sacrae" (1617) and "Cantica Sacra" (1618).The preface to "Cantiones Sacrae" states that the pieces were written "in the first city of the world" — meaning the centre of the Catholic faith, Rome.