From St. Ignatius who was taught by Polycarp who was taught by John the Apostle and by Justin Martyr:
http://www.ccel.org/ccel/schaff/anf01.v.vi.iv.htmlIgnatius to the Church at Philadelphia:
Ignatius, who is also called Theophorus, to the Church of God the Father, and our Lord Jesus Christ, which is at Philadelphia, in Asia, which has obtained mercy, and is established in the harmony of God, and rejoiceth unceasing in the passion of our Lord, and is filled with all mercy through his resurrection; which I salute in the blood of Jesus Christ, who is our eternal and enduring joy, especially if [men] are in unity with the bishop, the presbyters, and the deacons, who have been appointed according to the mind of Jesus Christ, whom He has established in security, after His own will, and by His Holy Spirit.
Take ye heed, then, to have but one Eucharist. For there is one flesh of our Lord Jesus Christ, and one cup to the unity of His blood; one altar; as there is one bishop, along with the presbytery and deacons, my fellow-servants: that so, whatsoever ye do, ye may do it according to [the will of] God.
I have confidence of you in the Lord, that ye will be of no other mind. 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 behoves you also, therefore, as “a peculiar people, and a holy
http://www.ccel.org/ccel/schaf...01.viii.ii.lxvi.htmlJustin Matyr
And this food is called among us Εὐχαριστία[ Literally, thanksgiving. See Matt. xxvi. 27.] of which no one is allowed to partake but the man who believes that the things which we teach are true, and who has been washed with the washing that is for the remission of sins, and unto regeneration, and who is so living as Christ has enjoined. For not as common bread and common drink do we receive these; but in like manner as Jesus Christ our Saviour, having been made flesh by the Word of God, had both flesh and blood for our salvation, so likewise have we been taught that the food which is blessed by the prayer of His word, and from which our blood and flesh by transmutation are nourished, is the flesh and blood of that Jesus who was made flesh.