As in 2 John 1, John referred to himself as “the Elder.” This could refer to his age, his position of authority as an apostle of the Lord, or even his relation to the addressed Gaius, who John considered his spiritual child. John showed great affection for Gaius in his use of “beloved,” but more importantly in the love expressed to him “in truth.” The love abounding from John to Gaius revolved around their commonality as those who loved the truth, and walked in the truth.

The purpose of this letter is expressed in two ways from verses 5-12. John commended Gaius for his walk in truth and love, which was shown in his hospitality toward the brethren. Yet, Gaius’ conduct is set in stark contrast to the conduct of Diotrephes who did the exact opposite. It is evident that John had in mind the sentiment expressed by Paul in the Galatian letter – “And let us not grow weary while doing good, for in due season we shall reap if we do not lose heart” (Galatians 6:9). John had an honest desire for Gaius to prosper in his physical things, especially in his health. His soul had already been prospering, and it would be good for him to prosper physically that he may not lose heart amidst the opposition of Diotrephes, and that he could continue to use his members as instruments of righteousness (cf. Romans 6:13).

John experienced great joy when news was brought to him about the conduct of Gaius. Gaius walked in the truth. He was a contributor to the cause of the gospel to the extent that his faith was well known, and commonly reported. The hearing of such produced in John what he described as, “no greater joy.” Gaius was as a child to John in that he was converted by John, or was greatly influenced by John’s teaching and guidance. Such an expression of joy should cause us to understand the precedence of spiritual things. John’s utmost desire was that those closest to him were faithful to God.