ChatGPT said:

Saint Arsenius, Archbishop of Peć, was born in Srem. He spent much of his life as a monk at the Žiča Monastery, under the spiritual guidance of Saint Sava (commemorated January 14). Because of his deep asceticism and devotion, Saint Sava appointed him as the monastery’s igumen (abbot).

When Serbia was invaded by the Hungarians, Saint Sava sent Saint Arsenius southward to find a safer location for a new episcopal see. Arsenius chose Peć, where he established a monastery and built a church first dedicated to the Holy Apostles, and later to the Lord’s Ascension.

Before departing for Jerusalem, Saint Sava named Saint Arsenius as his successor.

In 1236, Saint Sava reposed in Trnovo on his journey home, and Saint Arsenius urged King Vladislav to bring his relics back to Serbia for burial. After thirty-three years of faithfully leading the Church, Saint Arsenius fell asleep in the Lord in 1266. His holy relics were originally buried at the Peć Monastery and now rest in Ždrebaonik, Montenegro.

Troparion — Tone 4

In truth you were revealed to your flock as a rule of faith, / an image of humility and a teacher of abstinence; / your humility exalted you; / your poverty enriched you. / Hierarch Father Arsenius, / entreat Christ our God / that our souls may be saved.