A vicar general (previously, archdeacon) is the principal deputy of the bishop of a diocese for the exercise of administrative authority and possesses the title of local ordinary. As vicar of the bishop, the vicar general exercises the bishop's ordinary executive power over the entire diocese and, thus, is the highest official in a diocese or other particular church after the diocesan bishop or his equivalent in canon law. The title normally occurs only in Western Christian churches, such as the Latin Church of the Catholic Church and the Anglican Communion. Among the Eastern churches, the Mar Thoma Syrian Church of Kerala uses this title and remains an exception. The title for the equivalent officer in the Eastern churches is syncellus and protosyncellus. The term is used by many religious orders of men in a similar manner, designating the authority in the Order after its Superior General. Ecclesiastical structure In the Roman Catholic Church, a diocesan bishop must appoint at least one vicar general for his diocese, but may appoint more—dioceses whose territory is split into different states usually have one each. The vicar general by virtue of office is the bishop's agent in administration, acting as second-in-command for diocesan executive matters. (A priest in a separate office, the judicial vicar, serves a similar role with regard to the exercise of ordinary judicial power of governance in the diocese which is normally exercised in ecclesiastical courts.) Vicars general must be priests, auxiliary bishops, or coadjutor bishops—if a coadjutor bishop exists for a diocese, the diocesan bishop is to appoint him as a vicar general. Other auxiliary bishops are usually appointed vicars general or at least episcopal vicars. A vicar general is a local ordinary and, as such, acquires his powers by virtue of office and not by delegation. He is to possess a doctorate or at least a licentiate in canon law (JCL, JCD) or theology (STL, STD) or be truly expert in these fields. The similarly titled episcopal vicar shares in the bishop's ordinary executive power like the vicar general, except for the fact that the episcopal vicar's authority normally extends over only a particular geographic section of a diocese or over certain specific matters. These might include issues concerning religious institutes or the faithful of a different rite. These too must be priests or auxiliary bishops. The equivalent officer in the Eastern Churches is called the syncellus. Priests