He was a foreign correspondent for many years in the Middle East, the Balkans and Eastern Europe, where he reported for the Neue Zürcher Zeitung (NZZ) and the Swiss Radio DRS.
He was a lecturer in Ottoman History, Culture, Religion and Islamic Law at the University of Vienna (ULG) Balkan Studies.
He was President of the Association of Orthodox Churches in Switzerland (AGOK) and campaigned for Christians living, oppressed and persecuted in Islamic states.
[3][4][5][6] In 2010 he wrote an opinion on the unconstitutionality and particular danger of the organization Islamic Central Council Switzerland (IZRS).
Gstrein was able to rehabilitate the majority and continue his teaching as a lecturer for Balkan studies at the University of Vienna.