After his return to the Netherlands, De Jong taught philosophy at the seminary Rolduc and became responsible for youth, calling and evangelisation within the diocese. In 1994, bishop Wiertz made him chaplain of the
Basilica of Saint Servatius in
Maastricht, retaining his other functions. In 1995, he became priest for the students of Maastricht, and on December 11, 1998, he was made vicar-general of the diocese of Roermond. The next day,
Pope John Paul II appointed him as auxiliary bishop of Roermond and titular bishop of Cariana. He was consecrated as bishop on 6 February 1999, from
Franciscus Jozef Maria Wiertz, the Bishop of Roermond. On April 4, 1999, he became a
canon of the chapter of the cathedral of Roermond. On June 1, 2020,
Pope Francis gave him additional appointment as
apostolic administrator of the Military Ordinariate of Netherlands, while continuing to serve as auxiliary bishop of Roermond. == References ==