The apostles have preached the Gospel to us from the Lord Jesus Christ. Jesus Christ [has done so] from God. Christ, therefore, was sent by God, and the apostles by Christ. (1 Clement 42)

Apart from [Christ] let nothing attract you. For him I carry these chains around, these spiritual jewels. By them may I arise through your prayers, of which I request that I may always be a partaker, so that I may be found among the Christians of Ephesus, who have always been of the same mind with the apostles through the power of Jesus Christ. (Letter to the Ephesians 11)

Study ... to be established in the doctrines of the Lord and the apostles so that in everything, whatever you do, you may prosper in the flesh and spirit; in faith and love; in the Son, and the Father, and the Holy Spirit; in the beginning and the end; with your most admirable bishop, the well-compacted spiritual crown of your presbytery [i.e., body of elders], and the servants [deacons] who are according to God. (Letter to the Magnesians 13)

When he chose his own apostles who were to preach the Gospel, [he chose those] who were sinners above all sin, so that he might show that he came "not to call the righteous, but sinners to repentance" [Matt. 9:13]. (Letter of Barnabas 5)

For the apostles, in the memoirs composed by them, which are called Gospels, have delivered through them to us the things enjoined upon them: that Jesus took bread, and when he had given thanks, said, "Do this in memory of me; this is my body." After that, in the same way, having taken the cup and given thanks, he said, "This is my blood," and he gave it to them alone. (First Apology 66)

Such, then, is [the Valentinian] system, which neither the prophets announced, nor the Lord taught, nor the apostles delivered, but of which they boast that beyond all others they have a perfect knowledge. They gather their views by reading from what is not written. To use a common proverb, they strive to weave ropes of sand, while they endeavor to adapt with an air of probability to their own peculiar assertions the parables of the Lord, the sayings of the prophets, and the words of the apostles, in order that their scheme may not seem altogether without support. (Against Heresies I:8:1)

The church ... has received from the apostles and their disciples this faith ... (Against Heresies I:10:1)

We have learned from none others the plan of our salvation, than from those through whom the Gospel has come down to us, which they did at one time proclaim in public and, at a later period, by the will of God, handed down to us in the Scriptures, to be the ground and pillar of our faith. For it is unlawful to assert that they preached before they had perfect knowledge, as some even venture to say, boasting themselves as improvers of the apostles. For, after our Lord rose from the dead, they were invested with power from on high when the Holy Spirit came down, were filled from all, and had perfect knowledge. They departed to the ends of the earth, preaching the glad tidings of the good things [sent] from God to us and proclaiming the peace of heaven to men, who indeed do all equally and individually possess the Gospel of God.

Matthew also issued a written Gospel among the Hebrews in their own dialect, while Peter and Paul were preaching at Rome and laying the foundations of the Church. After their departure, Mark, the disciple and interpreter of Peter, did also hand down to us in writing what had been preached by Peter. Luke also, the companion of Paul, recorded in a book the Gospel preached by him. Afterwards, John, the disciple of the Lord, who also leaned upon his breast, did himself publish a Gospel during his residence at Ephesus in Asia. (Against Heresies III:1:1)

And others again reject the coming of the Son of God and the dispensation of His incarnation, which the apostles delivered and the prophets declared beforehand ... (Proof of the Apostolic Preaching, 99)

Accordingly, after one of these had been struck off, [Jesus] commanded the eleven others, on His departure to the Father, to "go and teach all nations, who were to be baptized into the Father, and into the Son, and into the Holy Spirit" [Matt. 28:19]. Immediately, therefore, so did the apostles, whom this designation [apostle] indicates as "the sent." Having, on the authority of a prophecy, which occurs in a psalm of David [Ps. 109:8], chosen Matthias by lot as the twelfth, into the place of Judas, they obtained the promised power of the Holy Spirit for the gift of miracles and of utterance; and after first bearing witness to the faith in Jesus Christ throughout Judaea, and founding churches (there), they next went forth into the world and preached the same doctrine of the same faith to the nations. They then in like manner founded churches in every city, from which all the other churches, one after another, derived the tradition of the faith, and the seeds of doctrine, and are every day deriving them, that they may become churches. Indeed, it is on this account only that they will be able to deem themselves apostolic, as being the offspring of apostolic churches. Every sort of thing must necessarily revert to its original for its classification. Therefore the churches, although they are so many and so great, comprise but the one primitive church, (founded) by the apostles, from which they all (spring). In this way all are primitive, and all are apostolic, whilst they are all proved to be one, in (unbroken) unity, by their peaceful communion, and title of brotherhood, and bond of hospitality,--privileges which no other rule directs than the one tradition of the selfsame mystery. (Prescription Against Heretics 20; brackets mine, parentheses in original)

Since the Lord Jesus Christ sent the apostles to preach, [our rule is] that no others ought to be received as preachers than those whom Christ appointed; for 'no one knows the Father except the Son, and him to whom the Son wishes to reveal him' [Matt. 11:27]. Nor does the Son seem to have revealed Him to any other than the apostles, whom he sent forth to preach. (Prescription Against Heretics 21)

Let nothing be innovated, says [Stephen, bishop of Rome], nothing maintained, except what has been handed down. From where is [his] tradition? Does it descend from the authority of the Lord and the Gospel or does it come from the commands and letters of the apostles? For that those things which are written must be done, God witnesses and admonishes, saying to Joshua … "The book of this Law shall not depart from your mouth, but you shall meditate on it day and night so that you may be careful to do all that is written in it" [Josh. 1:8]. Also, the Lord, when he sent his apostles, commands that the nations should be baptized and taught to observe all that he commanded. If, therefore, it is either prescribed in the Gospel or contained in the letters or Acts of the apostles,that those who came from any heresy should not be baptized, but only hands laid on them to repentance, let this divine and holy tradition be observed. But if everywhere heretics are called nothing other than adversaries and antichrists, if they are pronounced as people to be avoided, twisted and condemned by themselves, why is it that they should not be found worthy to be condemned by us, since it is obvious by the apostolic testimony that they are condemned by themselves? So no one ought to defame the apostles as though they had approved of the baptism of heretics, or had taken communion with them without the Church's baptism, when they, the apostles, wrote such things about the heretics. (Letter to Pompeius, Letter 73:2-3 in The Ante-Nicene Fathers, vol. V)

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