To be an apostle is to represent Jesus. This was the role of the original twelve. They lived and ate with Jesus and were commissioned to pass on who He was and who humanity had become as a result of His cross, resurrection and out-pouring at Pentecost.
Jesus was the apostle of His Father and the Plan. Jesus began the Kingdom of God. Apostolic ministry consists in multiplying what He began in the union with God that Jesus accomplished.
In its simplest sense “the apostolicity of the Church refers back to the original foundation of the Church once for all laid by Christ upon the apostles, but it also refers to the interpenetration of the existence and mission of the Church in its unswerving fidelity to that apostolic foundation” (The Trinitarian Faith, p 285).
Jesus was one with His Father and fully God in every way. It is Jesus along with the Holy Spirit and Father who live in us and thus join us to the life of God. Not only has Christ come in our flesh but the trinity actually lives in us, imparting their presence to us and joining us to the Fellowship of God. By this direct affinity and union, we represent God and share God with each other. This is the spirit of apostleship and the multiplication of heaven on earth.
Apostleship is never the multiplication of the abstractions of the law, but the multiplication of Christ in ourselves and in others.
We are richly blessed “to have inherited this "evangelical and apostolic framework," which defines and thus defends the deposit of faith once and for all given to the church by Jesus through his Apostles. By remaining true to this framework, the Church remains connected to Christ himself, who is the one Apostle in the absolute sense. That connection includes faithfully reading, understanding and teaching the deposit of faith given in Holy Scripture, and it includes faithful participation with Christ in his ongoing apostolic mission to the world, through his body, the Church.”
Note well the mandate and charge to pass on the deposit of faith that is Jesus and the apostles doctrine – named by Paul as ‘Christ in you’ and clearly separated from ‘other gospels’ and non-gospels or tares that are not actually connected to the Christ or our Father. Not connected because they are a continuation of the principles of the fall: The knowledge of good and evil and separation.