The elder unto the elect lady and her children, whom I love in the truth; and not I only, but also all they that have known the truth;
The elder — An appellation suited to a familiar letter, but upon a weighty subject.
To the elect — That is, Christian. Kuria is undoubtedly a proper name, both here and in 2 John 1:5; for it was not then usual to apply the title of lady to any but the Roman empress; neither would such a manner of speaking have been suitable to the simplicity and dignity of the apostle.
Whom — Both her and her children.
I love in the truth — With unfeigned and holy love.
 For the truth's sake, which dwelleth in us, and shall be with us for ever.
For the truth's sake, which abideth in us — As a living principle of faith and holiness.
 Grace be with you, mercy, and peace, from God the Father, and from the Lord Jesus Christ, the Son of the Father, in truth and love.
Grace takes away guilt; mercy, misery: peace implies the abiding in grace and mercy. It includes the testimony of God's Spirit, both that we are his children, and that all our ways are acceptable to him. This is the very foretaste of heaven itself, where it is perfected.
In truth and love — Or, faith and love, as St. Paul speaks. Faith and truth are here synonymous terms.
 I rejoiced greatly that I found of thy children walking in truth, as we have received a commandment from the Father.
I found of thy children — Probably in their aunt's house, 2 John 1:13.
Walking in the truth — In faith and love.
 And now I beseech thee, lady, not as though I wrote a new commandment unto thee, but that which we had from the beginning, that we love one another.
That which we had from the beginning — Of our Lord's ministry. Indeed it was, in some sense, from the beginning of the world.
That we may love one another — More abundantly.
 And this is love, that we walk after his commandments. This is the commandment, That, as ye have heard from the beginning, ye should walk in it.
And this is the proof of true love, universal obedience built on the love of God.
This — Love. Is the great commandment which ye have heard from the beginning - Of our preaching.
 For many deceivers are entered into the world, who confess not that Jesus Christ is come in the flesh. This is a deceiver and an antichrist.
Carefully keep what ye have heard from the beginning, for many seducers are entered into the world, who confess not Jesus Christ that came in the flesh - Who disbelieve either his prophetic, or priestly, or kingly office. Whosoever does this is the seducer - From God.
And the antichrist — Fighting against Christ.
 Look to yourselves, that we lose not those things which we have wrought, but that we receive a full reward.
That we lose not the things which we have wrought — Which every apostate does.
But receive a full reward — Having fully employed all our talents to the glory of him that gave them. Here again the apostle modestly transfers it to himself.
 Whosoever transgresseth, and abideth not in the doctrine of Christ, hath not God. He that abideth in the doctrine of Christ, he hath both the Father and the Son.
Receive this as a certain rule: Whosoever transgresseth - Any law of God.
Hath not God — For his Father and his God.
He that abideth in the doctrine of Christ — Believing and obeying it.
He hath both the Father and the Son — For his God.
 If there come any unto you, and bring not this doctrine, receive him not into your house, neither bid him God speed:
If any came to you — Either as a teacher or a brother.
And bring not this doctrine — That is, advance anything contrary to it.
Receive him not into your house — As either a teacher or a brother-Neither bid him God speed - Give him no encouragement therein.
 For he that biddeth him God speed is partaker of his evil deeds.
For he that biddeth him God speed — That gives him any encouragement, is accessory to his evil deeds.
 Having many things to write unto you, I would not write with paper and ink: but I trust to come unto you, and speak face to face, that our joy may be full.
Having many things to write, I was not minded to write now — Only of these, which were then peculiarly needful.
 The children of thy elect sister greet thee. Amen.
The children of thy elect or Christian sister - Absent, if not dead, when the apostle wrote this.