Episcopate and the Serbian Church
Jacob governed the Serbian Church during the early period of its leadership (1219–1346), when archbishops administered the ecclesiastical structure that Saint Sava had established as an autocephalous archbishopric in 1219, before the patriarchate was instituted in 1346.
He stood within the succession of early Serbian archbishops after Saint Sava: Arsenije I, Sava II, Danilo I, Joanikije I, Jevstatije I, Jacob, Jevstatije II, and Sava III. In some accounts he is also referred to as Jacob the New of Tuman.
His ministry was marked by special care for Serbian ascetics and by his support of monastic life. He provided liturgical books and church accessories to the monastery of Studenica.
Building and the Transfer of the See
Jacob renovated and founded churches during his tenure. He is associated with the transfer of the episcopal see from the Žiča Monastery to the Peć metochion, the seat of what would become the Patriarchate of Peć.
The archbishopric had been seated first at Žiča and, from the middle of the thirteenth century, increasingly at Peć. Žiča suffered destruction by the Cumans in the period around 1276–1292, which contextualizes the relocation of the see under Jacob.
According to the succession list of the Archbishopric of Peć, Jacob moved the seat to Peć in 1291 amid foreign invasion, likely completing the final transfer of the see. Between 1289 and 1290, within his tenure, the chief treasures of the ruined monastery were transferred to Peć.
Veneration
The Serbian Orthodox Church venerates Jacob as a saint, numbering him among the Saints of the Serbian Orthodox Church in the Eastern Orthodox tradition. Sources relate that he received his aureola for his saintly purity and Christian love.
The OCA Synaxarion commemorates Saint Jacob, Archbishop of Serbia, on February 3, listing him among the saints of that date; its entry notes that no fuller biographical information is available at this time, reflecting how relatively obscure this hierarch remains.