'God has appointed these in the church: first apostles...' (1 Corinthians 12:28). The Bible clearly states that God has set the apostles first in the church, but what exactly does that mean?
Some have argued that apostles had unquestionable and infallible authority (and so they also argue that there couldn't be any apostles today if we are to uphold the priciple of Sola Scriptura). However, this certainly doesn't follow from the text in question. 1 Corinthians 12:28 goes on to say 'second prophets, third teachers'. This is not a passage that sets up the apostleship in a highly exalted unique position over against the rest of the Church, but rather one that speaks of different positions and different ministries within the Church.
Others, such as D.A. Carson, have argued that this passage is referring to the chronological order in which various ministries and gifts appeared in the history of the Church. But this doesn't stack up either; the verse places 'varieties of tongues' in the last position, yet tongues were given at the founding of the Church on the day of Pentecost, whereas prophets and teachers (the 'second' and 'third') are not mentioned until much later in the book of Acts. So it cannot be a chronological list.
What then does it mean? F.F. Bruce speaks for many prominent commentators when he states that this verse marks out apostles, prophets and teachers 'as exercising, in Paul's estimation, the three most important ministries'. 'First apostles' speaks of the importance of the apostleship, whilst 'second prophets, third teachers' shows that the apostles are not alone in their importance and authority.
As a result, in the Apostolic Church we believe that the Apostle is 'the first office in church government' (Constitution, 126.96.36.199), yet they are not the only office in church government; after all, our Tenet states 'Church government by apostles, prophets, evangelists, pastors, teachers, elders and deacons.'
As the first office in Church government, the apostleship play an important role. In the words of the catechism, the apostleship 'reveals the mind of God in connection with the government of the Church'. The Apostleship functions in a way that the pastorate doesn't, bringing insight that no one else can. And so the apostleship is necessary for the good governance of the Church. God has set 'first apostles' and so we need 'first apostles'.