This is a quotation from Bishop Ignatius, the second bishop of the church of Antioch:
**Since therefore I have, in the persons before mentioned, beheld the whole multitude of you in faith and love, I exhort you to study to do all things with a divine harmony, while your bishop presides in the place of God, and your presbyters in the place of the assembly of the apostles, along with your deacons, who are most dear to me, and are entrusted with the ministry of Jesus Christ, who was with the Father before the beginning of time, and in the end was revealed. Do all then, imitating the same divine conduct, pay respect to one another, and let no one look upon his neighbour after the flesh, but continually love each other in Jesus Christ. Let nothing exist among you that may divide you; but be united with your bishop, and those that preside over you, as a type and evidence of your immortality. **
Ignatius Epistle to the Magnesians, chapter 6.
Notice how the bishop ‘presides in the place of God’. This is the terminology used to describe the High Priest over the Israelites as found in the Torah.
Notice how the “presbyters in the place of the assembly of the apostles”. The assembly of the apostles elsewhere in the epistles of Ignatius are called the Sandhedrin. The Sanhedrin were the elders of Israel who gave scriptural counsel to the High Priest.
Notice how the 'deacons are entrusted with the ministry of Jesus Christ". The deacon was the eyes and ears of the Bishop, who as stated earlier, represented God the Father on earth. In like manner, as Jesus Christ ministered to the people according the will of his Father.
This pattern of Bishops, presbyters (Sanhedrin) and deacons is also more fully delineated in the Apostolic Constitutions. In this document, deaconesses ministered to women, and they represented the Holy Spirit. There were also readers, and also the virgins and widows who prayers represented the altar of incense, whose prayers were a sweet fragrance unto God.:
**The bishop, he is the minister of the word, the keeper of knowledge, the mediator between God and you in the several parts of your divine worship. He is the teacher of piety; and, next after God, he is your father, who has begotten you again to the adoption of sons by water and the Spirit. He is your ruler and governor; he is your king and potentate; he is, next after God, your earthly god, who has a right to be honoured by you. For concerning him, and such as he, it is that God pronounces, “I have said, You are gods; and you are all children of the Most High.” And, “You shall not speak evil of the gods.” Exodus 22:28 For let the bishop preside over you as one honoured with the authority of God, which he is to exercise over the clergy, and by which he is to govern all the people. But let the deacon minister to him, as Christ does to His Father; and let him serve him unblameably in all things, as Christ does nothing of Himself, but does always those things that please His Father. Let also the deaconess be honoured by you in the place of the Holy Ghost, and not do or say anything without the deacon; as neither does the Comforter say or do anything of Himself, but gives glory to Christ by waiting for His pleasure. And as we cannot believe in Christ without the teaching of the Spirit, so let not any woman address herself to the deacon or bishop without the deaconess. Let the presbyters be esteemed by you to represent us the apostles, and let them be the teachers of divine knowledge; since our Lord, when He sent us, said, “Go and make disciples of all nations, baptizing them in the name of the Father, and of the Son, and of the Holy Ghost: teaching them to observe all things whatsoever I have commanded you.” Matthew 28:19 Let the widows and orphans be esteemed as representing the altar of burnt-offering; and let the virgins be honoured as representing the altar of incense, and the incense itself. **
The Constitutions of the Apostles, Book II, chapter XXVI
So the early church patterned themselves after the Levitical priesthood, and the way in which Jesus Christ and his apostles ministered to God and to the church in its beginning.
I think it is important to realize that the apostles were not described as bishops in the early church, but as the Sanhedrin. They appointed bishops over the various churches that had been evangelized and taught by them.