I. John greets Gaius (1-4)
A. John prays for him to have good health
B. John is glad he is walking in the truth
II. Obligation to support missionaries (5-8)
A. Gaius is faithful to missionaries (5-6a)
B. John exhorts Gaius to support them further (6b-8)
III. Diotrophes condemned (9-10)
A. Refuses apostolic teaching
B. Falsely accuses apostles
C. Doesn’t receive the brethren
D. Prevents others from receiving the brethren
E. Exercises unjust church discipline
IV. Demetrius commended (12)
John writes to Gaius, praying for his good health, and telling him he is glad that he is walking truth. Gaius is walking in the truth by practicing hospitality to Christian missionaries whom he does not know. John exhorts him to support them financially.
John condemns Diotrephes and his insubordination to the apostles as well as his unjust disunity. John concludes the brief letter telling Gaius he plans to speak with him face-to-face.