The Third Epistle of John, also penned by the apostle John, is addressed to Gaius, commending him for his hospitality and faithfulness to the truth. John contrasts Gaius' example with that of Diotrephes, a leader who resists the apostolic authority and hinders the work of the Gospel. John encourages Gaius to continue in his generous hospitality and support of fellow believers. 3 John emphasizes the importance of hospitality, truth, and love in the life of a believer and challenges readers to imitate those who do what is good.