St. Ignatius of Antioch said:
St. Ignatius of Antioch, Letter to the Magnesians, 6-7 (ANF, Vol., I)
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. He, being begotten by the Father before the beginning of time, was God the Word, the only-begotten Son, and remains the same for ever; for "of His kingdom there shall be no end," says Daniel the prophet. Let us all therefore love one another in harmony, and let no one look upon his neighbor according to the flesh, but in Christ Jesus. Let nothing exist among you which may divide you; but be united with your bishop, being through him subject to God in Christ.
As therefore the Lord does nothing without the Father, for says He, "I can of mine own self do nothing," so do you, neither presbyter, nor deacon, nor layman, do anything without the bishop. Nor let anything appear commendable to you which is destitute of his approval. For every such thing is sinful, and opposed[to the will of] God. Come together into the same place for prayer. Let there be one common supplication, one mind, one hope, with faith unblameable in Christ Jesus, than which nothing is more excellent. Do you all, as one man, run together into the temple of God, as unto one altar, to one Jesus Christ, the High Priest of the unbegotten God.
St. Ignatius of Antioch, Letter to the Trallians, 2-3 (ANF, Vol. I)
Be subject to the bishop as to the Lord, for "he watches for your souls, as one that shall give account to God." Wherefore also, you appear to me to live not after the manner of men, but according to Jesus Christ, who died for us, in order that, by believing in His death, you may by baptism be made partakers of His resurrection. It is therefore necessary, whatsoever things you do, to do nothing without the bishop. And be subject also to the presbytery, as to the apostles of Jesus Christ, in whom, if we live, we shall [at last] be found.
In like manner, let all reverence the deacons as an appointment of Jesus Christ, and the bishop as Jesus Christ, who is the Son of the Father, and the presbyters as the Sanhedrin of God, and assembly of the apostles. Apart from these, there is no Church. Concerning all this, I am persuaded that you are of the same opinion. For I have received the manifestations of your love, and still have it with me, in your bishop, whose very appearance is highly instructive, and his meekness of itself a power; whom I imagine even the ungodly must reverence.
St. Ignatius of Antioch, Letter to the Philadelphians, 4,1 (ANF, Vol. I)
Wherefore I write boldly to your love, which is worthy of God, and exhort you to have but one faith, and one [kind of] preaching, and one Eucharist. For there is one flesh of the Lord Jesus Christ; and His blood which was shed for us is one; one loaf also is broken to all [the communicants], and one cup is distributed among them all: there is but one altar for the whole Church, and one bishop, with the presbytery and deacons, my fellow-servants. Since, also, there is but one unbegotten Being, God, even the Father; and one only-begotten Son, God, the Word and man; and one Comforter, the Spirit of truth; and also one preaching, and one faith, and one baptism; and one Church which the holy apostles established from one end of the earth to the other by the blood of Christ, and by their own sweat and toil; it behooves you also, therefore, as "a peculiar people, and a holy nation," to perform all things with harmony in Christ.
St. Ignatius of Antioch, Letter to the Smyrnaeans, 8-9 (ANF, Vol. I)
See that you all follow the bishop, even as Jesus Christ does the Father, and the presbytery as you would the apostles; and reverence the deacons, as being the institution of God. Let no man do anything connected with the Church without the bishop. Let that be deemed a proper Eucharist, which is[administered] either by the bishop, or by one to whom he has entrusted it. Wherever the bishop shall appear, there let the multitude[of the people] also be; even as, wherever Jesus Christ is, there is the Catholic Church. It is not lawful without the bishop either to baptize or to celebrate a love-feast; but whatsoever he shall approve of, that is also pleasing to God, so that everything that is done may be secure and valid... It is not lawful without the bishop either to baptize, or to offer, or to present sacrifice, or to celebrate a love-feast. But that which seems good to him, is also well-pleasing to God, that everything you do may be secure and valid.
And say I, Honor God indeed, as the Author and Lord of all things, but the bishop as the high-priest, who bears the image of God—of God. inasmuch as he is a ruler, and of Christ, in his capacity of a priest. After Him, we must also honor the king. For there is no one superior to God, or even like to Him, among all the beings that exist. Nor is there any one in the Church greater than the bishop, who ministers as a priest to God for the salvation of the whole world. Nor, again, is there any one among rulers to be compared with the king, who secures peace and good order to those over whom he rules. He who honors the bishop shall be honored by God, even as he that dishonors him shall be punished by God. For if he that rises up against kings is justly held worthy of punishment, inasmuch as he dissolves public order, of how much sorer punishment, do you suppose, shall he be thought worthy, who presumes to do anything without the bishop, thus both destroying the[Church's] unity, and throwing its order into confusion? For the priesthood is the very highest point of all good things among men, against which whosoever is mad enough to strive, dishonors not man, but God, and Christ Jesus, the First-born, and the only High Priest, by nature, of the Father. Let all things therefore be done by you with good order in Christ. Let the laity be subject to the deacons; the deacons to the presbyters; the presbyters to the bishop; the bishop to Christ, even as He is to the Father.