Gaius mine host, and of the whole church, saluteth you, Romans 16:23.
If you ask just about any scholar when 3rd John was written, they will probably tell you that is was written about 90AD. There are some who give it an earlier date, but those are rare. We shall see that it was written about the time of the Epistle to the Romans. There are some who look to the trouble that John had with Diotrephes and conclude that the author couldn't have been the Apostle John since apostles were held in such great esteem.
Whoever thinks that way has probably not read 2nd Timothy 4:10-16. Instead, John, the author of 3rd John sounds remarkably like the Apostle Paul when he reckoned with the Corinthian Church.
1st Corinthians 4:18 Now some are puffed up, as though I would not come to you.
1st Corinthians 4:19 But I will come to you shortly, if the Lord will, and will know, not the speech of them which are puffed up, but the power.
1st Corinthians 4:20 For the kingdom of God is not in word, but in power.
1st Corinthians 4:21 What will ye? shall I come unto you with a rod, or in love, and in the spirit of meekness?
It was not a good idea to cross swords with an apostle. As Elymas the sorcerer learned in Acts 13, an apostle could exercise apostolic power. And now, behold, the hand of the Lord is upon thee, and thou shalt be blind, not seeing the sun for a season. And immediately there fell on him a mist and a darkness; and he went about seeking some to lead him by the hand, Acts 13:10, 11.
John made it clear when he spoke of Diotrephes that he intended to do something about his behavior when he arrived. 3rd John 1:9 I wrote unto the church: but Diotrephes, who loveth to have the preeminence among them, receiveth us not.
3rd John 1:10 Wherefore, if I come, I will remember his deeds which he doeth, prating against us with malicious words: and not content therewith, neither doth he himself receive the brethren, and forbiddeth them that would, and casteth them out of the church.
3rd John is written to Gaius but that appears to be a blind. Gaius was Paul's host when Paul wrote to the Romans. 3rd John is written to Gaius but it is written for the Apostle Paul. Both apostles shared a church in Ephesus. Paul wrote to seven churches, John wrote to seven churches. They had two churches in common. Ephesus received letters from both apostles. John wrote to Laodicea and the Apostle Paul wrote to Timothy while Paul was in Laodicea and he wanted that letter shared. The first to Timothy was written from Laodicea, which is the chiefest city of Phrygia Pacatiana, 1st Timothy subscript. And when this epistle is read among you, cause that it be read also in the church of the Laodiceans; and that ye likewise read the epistle from Laodicea, Colossians 4:16.
The twelve apostles were directed to live off of their host's benevolence.
Matthew 10:6 But go rather to the lost sheep of the house of Israel.
Matthew 10:7 And as ye go, preach, saying, The kingdom of heaven is at hand.
Matthew 10:8 Heal the sick, cleanse the lepers, raise the dead, cast out devils: freely ye have received, freely give.
Matthew 10:9 Provide neither gold, nor silver, nor brass in your purses,
Matthew 10:10 Nor scrip for your journey, neither two coats, neither shoes, nor yet staves: for the workman is worthy of his meat.
The Apostle Paul extended those directions to those who labored among the Gentiles, yet he himself partook not.
1st Corinthians 9:9 For it is written in the law of Moses, Thou shalt not muzzle the mouth of the ox that treadeth out the corn. Doth God take care for oxen?
1st Corinthians 9:10 Or saith he it altogether for our sakes? For our sakes, no doubt, this is written: that he that ploweth should plow in hope; and that he that thresheth in hope should be partaker of his hope.
1st Corinthians 9:11 If we have sown unto you spiritual things, is it a great thing if we shall reap your carnal things?
1st Corinthians 9:12 If others be partakers of this power over you, are not we rather? Nevertheless we have not used this power; but suffer all things, lest we should hinder the gospel of Christ.
1st Corinthians 9:13 Do ye not know that they which minister about holy things live of the things of the temple? and they which wait at the altar are partakers with the altar?
1st Corinthians 9:14 Even so hath the Lord ordained that they which preach the gospel should live of the gospel.
1st Corinthians 9:15 But I have used none of these things: neither have I written these things, that it should be so done unto me: for it were better for me to die, than that any man should make my glorying void.
1st Corinthians 9:16 For though I preach the gospel, I have nothing to glory of: for necessity is laid upon me; yea, woe is unto me, if I preach not the gospel!
1st Corinthians 9:17 For if I do this thing willingly, I have a reward: but if against my will, a dispensation of the gospel is committed unto me.
1st Corinthians 9:18 What is my reward then? Verily that, when I preach the gospel, I may make the gospel of Christ without charge, that I abuse not my power in the gospel.
It was a mark of the Apostle Paul's ministry and those who labored with him that they took nothing of the Gentiles.
3rd John 1:5 Beloved, thou doest faithfully whatsoever thou doest to the brethren, and to strangers;
3rd John 1:6 Which have borne witness of thy charity before the church: whom if thou bring forward on their journey after a godly sort, thou shalt do well:
3rd John 1:7 Because that for his name's sake they went forth, taking nothing of the Gentiles.
Perhaps the greatest clue that that 3rd John was meant for Paul to read while he abode with Gaius is found in verse 14; But I trust I shall shortly see thee, and we shall speak face to face. Peace be to thee. Our friends salute thee. Greet the friends by name, 3rd John 1:14. Paul ended the Epistle to the Romans by greeting the brethren by name.
Romans 16:3 Greet Priscilla and Aquila my helpers in Christ Jesus:
Romans 16:4 Who have for my life laid down their own necks: unto whom not only I give thanks, but also all the churches of the Gentiles.
Romans 16:5 Likewise greet the church that is in their house. Salute my wellbeloved Epaenetus, who is the firstfruits of Achaia unto Christ.
Romans 16:6 Greet Mary, who bestowed much labour on us.
Romans 16:7 Salute Andronicus and Junia, my kinsmen, and my fellowprisoners, who are of note among the apostles, who also were in Christ before me.
Romans 16:8 Greet Amplias my beloved in the Lord.
Romans 16:9 Salute Urbane, our helper in Christ, and Stachys my beloved.
Romans 16:10 Salute Apelles approved in Christ. Salute them which are of Aristobulus' household.
Romans 16:11 Salute Herodion my kinsman. Greet them that be of the household of Narcissus, which are in the Lord.
Romans 16:12 Salute Tryphena and Tryphosa, who labour in the Lord. Salute the beloved Persis, which laboured much in the Lord.
Romans 16:13 Salute Rufus chosen in the Lord, and his mother and mine.
Romans 16:14 Salute Asyncritus, Phlegon, Hermas, Patrobas, Hermes, and the brethren which are with them.
Romans 16:15 Salute Philologus, and Julia, Nereus, and his sister, and Olympas, and all the saints which are with them.
Romans 16:16 Salute one another with an holy kiss. The churches of Christ salute you.
Romans 16:17 Now I beseech you, brethren, mark them which cause divisions and offences contrary to the doctrine which ye have learned; and avoid them.
Romans 16:18 For they that are such serve not our Lord Jesus Christ, but their own belly; and by good words and fair speeches deceive the hearts of the simple.
Romans 16:19 For your obedience is come abroad unto all men. I am glad therefore on your behalf: but yet I would have you wise unto that which is good, and simple concerning evil.
Romans 16:20 And the God of peace shall bruise Satan under your feet shortly. The grace of our Lord Jesus Christ be with you. Amen.
Romans 16:21 Timotheus my workfellow, and Lucius, and Jason, and Sosipater, my kinsmen, salute you.
Romans 16:22 I Tertius, who wrote this epistle, salute you in the Lord.
Romans 16:23 Gaius mine host, and of the whole church, saluteth you. Erastus the chamberlain of the city saluteth you, and Quartus a brother.
Finishing note: There will be some who wonder why I would quote the subscript to 1st Timothy. I do so because I am an unapologetic King James Bible believer and I believe it to be scripture.