The 17th century Flemish biographer Cornelis de Bie wrote in his Het Gulden Cabinet that Jan Thomas was a pupil of Peter Paul Rubens.
Modern scholarship tends to regard Jan Thomas as one of the many collaborators in Rubens' workshop who assisted with large commissions such as the decorations for the Torre de la Parada, the hunting lodge of the Spanish king (1636–1638).
[5] In 1652 Jan Thomas' third child was baptized in the St. James' Church in Antwerp, which is evidence that he was then still living in that city.
It is believed that Jan Thomas left Antwerp in 1654 to work as a painter for the bishop of Mainz Johann Philipp von Schönborn one of the important courts at that time.
[5] In Vienna he received commissions from the imperial court and painted the portraits of Leopold I and his wife Margaret Theresa in theater costume.
[6] Jan Thomas also received commissions from the higher clergy and the aristocracy, such as the House of Zrinski or Zrínyi.
[3] Like his contemporary Frans Wouters, many of his works translate the monumental Baroque style of Peter Paul Rubens into the small context of cabinet paintings.
One of these works in mezzotint is a portrait of Titian from 1661, which was dedicated to Empress Eleonora, widow of the father of Leopold I, Emperor Ferdinand III.
He made engravings of his own compositions as well as of the works of other artists such as Rubens, Anthony van Dyck, Gerard Dou and Giovanni Ambrogio Figino.
This may be a pure genre scene or a vanitas allegory reminding the viewer of the temporary nature of all humanly endeavors.