1 The elder,
To my dear friend Gaius, whom I love in the truth.
2 Dear friend, I pray that you may enjoy good health and that all may go well with you, even as your soul is getting along well. 3 It gave me great joy when some believers came and testified about your faithfulness to the truth, telling how you continue to walk in it. 4 I have no greater joy than to hear that my children are walking in the truth.
5 Dear friend, you are faithful in what you are doing for the brothers and sisters,[a] even though they are strangers to you. 6 They have told the church about your love. Please send them on their way in a manner that honors God. 7 It was for the sake of the Name that they went out, receiving no help from the pagans. 8 We ought therefore to show hospitality to such people so that we may work together for the truth.
9 I wrote to the church, but Diotrephes, who loves to be first, will not welcome us. 10 So when I come, I will call attention to what he is doing, spreading malicious nonsense about us. Not satisfied with that, he even refuses to welcome other believers. He also stops those who want to do so and puts them out of the church.
11 Dear friend, do not imitate what is evil but what is good. Anyone who does what is good is from God. Anyone who does what is evil has not seen God. 12 Demetrius is well spoken of by everyone—and even by the truth itself. We also speak well of him, and you know that our testimony is true.
13 I have much to write you, but I do not want to do so with pen and ink. 14 I hope to see you soon, and we will talk face to face.
Peace to you. The friends here send their greetings. Greet the friends there by name.
Since Gaius is not exactly a household name or what people name their kids anymore, here is his background in the New Testament. There are actually 4 people by the name of Gaius in the New Testament, but this is regarding the Gaius in John letter. This is taken from Gotquestions.org
Gaius, John’s friend. The Epistle of 3 John is addressed to a man named Gaius who was a member of an unnamed church that John had the oversight of (3 John 1:1). John calls this man a “dear friend” (verses 1, 2, and 11). Gaius is commended for his hospitality to traveling preachers of the gospel (verses 5, 6 and 8); for his faithfulness (verse 5); for his love (verse 6); and for his walking in the truth (verse 3). According to tradition this Gaius may be the one whom John appointed as bishop of Pergamum.
Two of the Gaiuses mentioned in the Bible were known for their hospitality, and that is probably why John Bunyan, needing a name for his innkeeper in The Pilgrim’s Progress, choose the name “Gaius.” Gaius’s name means “happy” or “one who rejoices,” and the men who bore that name in Scripture seem to have known the joy that comes from serving the Lord.
In the letter a man named Diotrephese is also mentioned. But he is mentioned because he exhibits all the opposite traits of Gaius. He is: selfish, unwelcoming, spreading bad rumors about John, refuses to welcome other believers, and even stops those who do so and kicks them out of the church. What a pleasant guy? It's hard to imagine what would drive anyone to be under his leadership and teaching.
But he is not the purpose of this letter, but it is Gaius' hospitable treatment of other believers that John commends. Apparently Gaius not only showered them with hospitality, but helped them on their way most likely with other resources they needed for their mission work. John says Gaius' actions are being reported in the church, which builds forward momentum and it energizes others to do the same.
Often our churches can be inward focused, just looking how we can grow. But we are part of a larger body of Christ. We need to support others who are advancing the cause of Christ, especially missionaries looking to bring Jesus to previously un-reached people groups. We can do this personally, as well as in our churches. This is the time of year that many para church groups and missionaries look for support. How might you support them with prayer, hospitality and resources?
Finally, who are those near you who need the hospitality of Christ? Do welcome others in our lives who need help at a critical phase in their lives? Do we create space to be able to meet a need that arises in the body. Hospitality is an important gift in the church. When it is exercised the church becomes invitational and it draws people to Christ!