 With the consent of Great Prince Vasily III of Moscow, he was consecrated Archbishop of Novgorod on January 15, 1506, but only served a little over three years.In July 1509, at the Sobor that considered the conflict between him and Joseph Volotsky (the latter was under Serapion's episcopal jurisdiction but had directly appealed to Simon, Metropolitan of Moscow - an act that Serapion deemed to be uncanonical), and his letter of complaint, in which he said Joseph had abandoned heavan (meaning he had abandoned his rightful bishop) and descended to earth.The grand prince took this as a personal insult, that Serapion was claiming the local prince was divinely mandated and Grand Prince Vasilii III was mundane.