Timothy was of Hungarian ethnicity. He was styled as "magister", confirming his university degree. He first appears in contemporary documents in 1259, when he was a member of Cardinal Stephen Báncsa's familia in Orvieto. There he functioned as chamberlain and also held the church position of canon of Pécs. Following that he was styled as canon of Zala, then dean of Valkó. His benefice also contained four chapels in the Diocese of Győr. In early 1263, the Cathedral Chapter of Zagreb nominated the cardinal's namesake nephew bishop. His appointment was petitioned to the Roman Curia, where Pope Urban IV requested the opinion of Cardinal Báncsa. After consultations, Stephen II Báncsa's nomination was refused confirmation on 24 September 1263, because he was under the minimum age for a bishop. Instead of him, the cardinal suggested Timothy to become the Bishop of Zagreb. Timothy was elected by some members of the chapter in the same month, but other canons denied the legality of the election. King Béla IV of Hungary also protested against the pope's decision, referring to his "incapability to become a royal advisor". Béla was angered by the fact too that Pope Urban allowed to Cardinal Báncsa to be free to distribute Timothy's benefices in Hungary among his relatives. In this period, royal charters considered the bishopric of Zagreb as sede vacante. In December 1263, Timothy was referred to as bishop-elect and papal chaplain. He resided in Báncsa's court at Viterbo. Finally, Pope Urban confirmed his election in 1264. Already during the pontificate of Pope Clement IV, Béla IV sent a royal delegation led by his loyal clergyman Demetrius, archdeacon of Bars to Rome in October 1265 to protest against Timothy's confirmation. Demetrius expressed Timothy's incompetence before the Roman Curia, arguing with his lowborn social status. The pope was outraged by the archdeacon's claim and refused his request. Béla sent again his delegation in April 1266, but Pope Clement did not change his decision. To indicate his goodwill, he appointed Demetrius as papal chaplain. Following that Béla IV abandoned the case and acknowledged Timothy's election. Timothy was commissioned to guard the castle of Garics, a centre of a border ispánate in Križevci County, in 1272. He complied with that request at his own expense. By formalizing the status quo, Timothy and his diocese were granted the castle of Garics and Gerzence ispánate by Ladislaus IV in March 1277. Taking advantage of the chaotic situation, which characterized the young Ladislaus' reign, the three brothers of the Kőszegi family, Nicholas, Ivan and Henry plundered the estates of the Diocese of Zagreb at various times in early 1281. According to Timothy's letter to Archbishop Lodomer, the Kőszegis and their henchmen completely devastated and pillaged the episcopal estate of Vaska and the surrounding lands. Timothy also complained that Ivan and Nicholas arbitrarily usurped the Gerzence lordship, a rightful possession of his diocese since 1277 after a donation of Ladislaus IV. According to his letter, the Kőszegi brothers unlawfully collected the tithe in the territory of his diocese, while Nicholas also captured and robbed the senior officials of the bishopric. The Kőszegis' henchman, a certain notorious highwayman Wrycz tortured the captured clerics until they gave them the treasures. For their crimes, Timothy excommunicated the three Kőszegi brothers in Virovitica on 25 March 1281. Timothy died on 4 April 1287.
