[3] John bought a portion in Mita, Trencsén County in 1210, expanding the possessions of the bishopric there.
He bought half part of Biccse (today Bytča, Slovakia) from castle warriors in Trencsén County.
[4] Alongside papal legate Cardinal Gregorius de Crescentio [fr] and Leopold VI, Duke of Austria, John mediated between King Ottokar I of Bohemia and Andrew, Bishop of Prague in their investiture controversy in 1221.
The Bohemian king confirmed the lost privileges of the Diocese of Prague in June 1221, then the papal legate lifted the excommunication over the kingdom imposed by Andrew earlier.
Alongside other prelates from Austria and Poland, the name of John appeared among the testimonies of Ottokar's royal charter.