2:1 - My little children, these things write I unto you, that all of you sin not. And if any man sin, we have an advocate with the Father, Jesus Christ the righteous:

Irenaeus Against Heresies Book III
Wherefore we have need of the dew of God, that we be not consumed by fire, nor be rendered unfruitful, and that where we have an accuser there we may have also an Advocate,[318]
Tertullian On Modesty
All the more fully: "Little children, these things have I written to you, lest ye sin; and if ye shall have sinned, an Advocate we have with God the Father, Jesus Christ the righteous; and, He is the propitiation for our sins."[245]
Origen de Principiis Book II
And since we have made mention of the Paraclete, and have explained as we were able what sentiments ought to be entertained regarding Him; and since our Saviour also is called the Paraclete in the Epistle of John, when he says, "If any of us sin, we have a Paraclete with the Father, Jesus Christ the righteous, and He is the propitiation for our sins; "[113]
Peter of Alexandria Canonical Epistle
" "And if any man sin," says he, "we have an Advocate with the Father, Jesus Christ the righteous: and He is the propitiation for our sins."[42]
Origen Commentary on John Book I
" And in his Catholic Epistle John says that He is a Paraclete for our souls with the Father, as thus:[107]
Origen Commentary on John Book VI
-what and how great things must be said of the Lamb of God, who was sacrificed for this very reason, that He might take away the sin not of a few but of the whole world, for the sake of which also He suffered? If any one sin, we read,[164]

2:2 - And he is the propitiation for our sins: and not for our's only, but also for the sins of the whole world.

Clement of Alexandria The Instructor Book III
Hereby know we that we are in Him. He that saith he abideth in Him, ought himself to walk even as He also walked."[211]
Origen Against Celsus Book III
" Such indeed does the Gospel invite, in order to make them better; but it invites also others who are very different from these, since Christ is the Saviour of all men, and especially of them that believe, whether they be intelligent or simple; and "He is the propitiation with the Father for our sins; and not for ours only, but also for the sins of the whole world."[160]
Origen Against Celsus Book IV
and His Christ to be the "propitiation for our sins, and not for ours only, but also for the sins of the whole world."[111]
Origen Against Celsus Book VIII
Accordingly, we worship with all our power the one God, and His only Son, the Word and the Image of God, by prayers and supplications; and we offer our petitions to the God of the universe through His only-begotten Son. To the Son we first present them, and beseech Him, as "the propitiation for our sins,"[29]
Cyprian Epistle LI
And if any man sin, we have an Advocate with the Father, Jesus Christ the Supporter: and He is the propitiation for our sins."[32]

2:3 - And hereby we do know that we know him, if we keep his commandments.

Cyprian Epistle XXIV
He that saith he knoweth Him, and keepeth not His commandments, is a liar, and the truth is not in him."[3]

2:4 - He that says, I know him, and keeps not his commandments, is a liar, and the truth is not in him.

Clement of Alexandria Stromata Book III
Nos enim didicimus libertatem, qua Dominus noster nos liberat a voluptatibus, eta cupiditatibus, et aliis perturbationibus solvens. "Qui dicit: Novi Dominum, et mandata ejus non setvat, mendax est, et in eo veritas non est,"[49]

2:6 - He that says he abides in him ought himself also so to walk, even as he walked.

Origen de Principiis Book IV
according to the words of Scripture: "He that saith that he believeth in Christ, ought so to walk, as He also walked."[42]
Cyprian Epistle LV
For this is to wish to be found with Christ, to imitate that which Christ both taught and did, according to the Apostle John, who said, "He that saith he abideth in Christ, ought himself also so to walk even as He walked."[5]
Cyprian Treatise IX On the Advantage of Patience
But if we also, beloved brethren, are in Christ; if we put Him on, if He is the way of our salvation, who follow Christ in the footsteps of salvation, let us walk by the example of Christ, as the Apostle John instructs us, saying, "He who saith he abideth in Christ, ought himself also to walk even as He walked."[20]
Cyprian Treatise XII Three Books of Testimonies Against the Jews
Of this same thing in the Epistle of John: "He who saith he abideth in Christ, ought himself also to walk even as He walked."[451]

2:9 - He that says he is in the light, and hates his brother, is in darkness even until now.

Cyprian Treatise X On Jealousy and Envy
And again: "He that saith he is in the light, and hateth his brother, is in darkness even until now, and walketh in darkness, and knoweth not whither he goeth, because that darkness hath blinded his eyes."[25]
Cyprian Treatise XII Three Books of Testimonies Against the Jews
Also in the same place: "He who saith he is in the light, and hateth his brother, is a liar, and walketh in darkness even until now."[386]

2:11 - But he that hates his brother is in darkness, and walks in darkness, and knows not where he goes, because that darkness has blinded his eyes.

A Treatise Against the Heretic Novatian by an Anonymous Bishop
Hast thou not read, that "he who hateth his brother is in darkness, and walketh in darkness, and knoweth not whither he goeth, because the darkness hath blinded his eyes? "[45]

2:12 - I write unto you, little children, because your sins are forgiven you for his name's sake.

Origen Commentary on John Book X
"After this[1]

2:15 - Love not the world, neither the things that are in the world. If any man love the world, the love of the Father is not in him.

Cyprian Treatise II On the Dress of Virgins
And the world passeth away, and the lust thereof: but he that doeth the will of God abideth for ever, even as God also abideth for ever."[21]
Cyprian Treatise VII On the Mortality
And the world shall pass away, and the lust thereof; but he who doeth the will of God abideth for ever, even as God abideth for ever."[49]
Cyprian Treatise XII Three Books of Testimonies Against the Jews
And the world shall pass away with its lust. But he that doeth the will of God abideth for ever, even as God abideth for ever."[452]
Origen Commentary on Matthew Book XII
If therefore any one of us wishes to be taken by Jesus, and led up by Him into the high mountain, and be deemed worthy of beholding His transfiguration apart, let him pass beyond the six days, because he no longer beholds the things which are seen, nor longer loves the world, nor the things in the world,[228]

2:16 - For all that is in the world, the lust of the flesh, and the lust of the eyes, and the pride of life, is not of the Father, but is of the world.

Tertullian On Modesty
, with its own vicious nature, easily indulging concupiscence after whatever it had seen to be "attractive to the sight,"[70]

2:17 - And the world passes away, and the lust thereof: but he that does the will of God abides for ever.

Cyprian Treatise XII Three Books of Testimonies Against the Jews
In the Epistle of John: "But he that doeth the will of God abideth for ever, even as He Himself also abideth for ever."[509]

2:18 - Little children, it is the last time: and as all of you have heard that antichrist shall come, even now are there many antichrists; whereby we know that it is the last time.

Irenaeus Against Heresies Book III
Know ye therefore, that every lie is from without, and is not of the truth. Who is a liar, but he that denieth that Jesus is the Christ? This is Antichrist."[288]
Irenaeus Against Heresies Book IV
foreseeing by the Spirit those weak-minded persons who should be led astray.[4]
Clement of Alexandria Stromata Book III
Ex nobis exierunt, sed non erant ex nobis. Nam si fuissent ex nobis, permansissent utique nobiscum."[51]
Tertullian On Fasting
And how is it that he enjoins duties which belong to our God, and enjoins them to be offered to none other than our God? Either contend that the devil works with our God, or else let the Paraclete be held to be Satan. But you affirm it is "a human Antichrist: "for by this name heretics are called in John.[90]
Dubious Hippolytus Fragments
and even now are there many antichrists;[35]
Cyprian Epistle LXIX
They went out from us, but they were not of us; for if they had been of us, no doubt they would have continued with us."[20]
Cyprian Epistle LXXV
They went out from us, but they were not of us; for if they had been of us, they would have continued with us."[3]
Origen Commentary on Matthew Book XI
that is, at the consummation of the age in regard to which we may fitly say what is found in the Epistle of John, "It is the last hour."[2]

2:19 - They went out from us, but they were not of us; for if they had been of us, they would no doubt have continued with us: but they went out, that they might be made manifest that they were not all of us.

Tertullian The Prescription Against Heretics
John, ) "but they were not of us. If they had been of us, they would no doubt have continued with us."[33]
Cyprian Epistle LIV
has once learned, never departs from Him at all, and that those are the Church who remain in the house of God; but that, on the other hand, they are not the plantation planted by God the Father, whom we see not to be established with the stability of wheat, but blown about like chaff by the breath of the enemy scattering them, of whom John also in his epistle says, "They went out from us, but they were not of us; for if they had been of us, no doubt they would have continued with us."[32]
Cyprian Treatise I On the Unity of the Church
The Apostle John execrates and severely assails these, when he says, "They went forth from us, but they were not of us; for if they had been of us, surely they would have continued with us."[33]

2:20 - But all of you have an anointing from the Holy One, and all of you know all things.

Shepherd of Hermas Commandment Third
They therefore who lie deny the Lord, and rob Him, not giving back to Him the deposit which they have received. For they received from Him a spirit free from falsehood.[3]
Theophilus to Autolycus Book I
r house is beautiful and serviceable when it has not been anointed? And what man, when he enters into this life or into the gymnasium, is not anointed with oil? And what work has either ornament or beauty unless it be anointed and burnished? Then the air and all that is under heaven is in a certain sort anointed by light and spirit; and are you unwilling to be anointed with the oil of God? Wherefore we are called Christians on this account, because we are anointed with the oil of God.[18]

2:21 - I have not written unto you because all of you know not the truth, but because all of you know it, and that no lie is of the truth.

Cyprian Treatise XII Three Books of Testimonies Against the Jews
In the Epistle of John: "If our heart blame us not, we have confidence towards God; and whatever we ask, we shall receive from Him."[732]

2:22 - Who is a liar but he that denies that Jesus is the Christ? He is antichrist, that denies the Father and the Son.

Epistle of Ignatius to the Antiochians
And he that rejects the incarnation, and is ashamed of the cross for which I am in bonds, this man is antichrist.[24]
Tertullian Against Praxeas
John, moreover, brands that man as "a liar" who "denieth that Jesus is the Christ; "whilst on the other hand he declares that "every one is born of God who believeth that Jesus is the Christ."[398]

2:23 - Whosoever denies the Son, the same has not the Father: he that acknowledges the Son has the Father also.

Cyprian Treatise XI Exhortation to Martyrdom Addressed to Fortunatus
John too: "Whosoever denieth the Son, the same hath not the Father; he that acknowledgeth the Son, hath both the Son and the Father."[39]
Cyprian Treatise XII Three Books of Testimonies Against the Jews
Also in the Epistle of John: "Whosoever denieth the Son, the same also hath not the Father. He that confesseth the Son, hath both the Son and the Father."[300]

2:27 - But the anointing which all of you have received of him abides in you, and all of you need not that any man teach you: but as the same anointing teaches you of all things, and is truth, and is no lie, and even as it has taught you, all of you shall abide in him.

Cyprian Epistle LXIX
It is also necessary that he should be anointed who is baptized; so that, having received the chrism,[11]