A native of Burgeis near Ötz, he probably came to Bohemia already as a trained sculptor. He first worked as a journeyman in the workshop of Matyáš Bernard Braun, then around 1728 he became an independent master, married and settled in Jaroměř.
In the same year, he visited Žďár nad Sázavou where he eventually stayed for a long time due to work assignments he was awarded betwen 1729 to 1739. The sculptures on the main altar of the abbey church in Žďár nad Sázavou are attributed to him and he was also the author of the model of the processional statue of St John of Nepomuk, which was later made from silver by the Prague goldsmith Jan Norbert Diesbach. Theny later decorated the stretcher for this statue with reliefs – unlike the statue itself, the stretcher has survived to this day.
With the arrival of this strong artistic personality, the artistic style of the great baroque sculptor, Matthias Bernard Braun, fully affected the monastery of Žďár nad Sázavou. Theny was Braun's youngest direct collaborator and at the same time his compatriot, as the great master also came from Burgeis near Ötz. He participated on important Braun's works in the most fruitful period of his workshop in the years 1717-1720. Theny's mark is visible in Kuks, in one of Braun's most important masterpieces, where Theny was his main collaborator. By 1723, Theny was already working independently on the demanding composition of the main altar of the Marian pilgrimage church in Stará Boleslav. Theny gained such a recognition of Braun that his master entrusted him with the decoration of the monastery church in Kladruby. In the years 1726-1728, Theny created the impressive main altar and the decoration of the choir benches for the architect Santini. In Jaroměř and Kladruby, he worked together with Jiří František Pacák. The difference between the two is not very clear at first, but in later works, Theny, in contrast to Pacák's somewhat difficult and to some extent routine expressive concept, establishes balance in movement and expressive brightness.
