Third John is a personal letter from the Apostle John to a Christian leader named Gaius. The primary purpose of the letter is to commend Gaius for his faithfulness and hospitality toward traveling Christian missionaries. John encourages Gaius to continue supporting these ministers of the gospel, emphasizing that doing so makes him a fellow worker for the truth. In contrast, John warns against a man named Diotrephes, a church leader who was proud, power-hungry, and refused to welcome the missionaries. Diotrephes not only rejected John's authority but also slandered him and excommunicated church members who showed hospitality to the missionaries. The letter also commends Demetrius, who seems to have been the letter carrier, as a man with a good testimony. Ultimately, 3 John is a practical exhortation to walk in truth and love, demonstrated through hospitality and support for those who serve Christ, while rejecting the influence of selfish and divisive leaders within the church.

The book of 3 John provides a timeless model for Christian hospitality and discernment. It encourages believers to generously support those who are faithfully ministering the gospel, recognizing that such partnership is vital for the advancement of God's kingdom. As C.S. Lewis might suggest, this practical love and support for one another is a tangible outworking of our inner faith. The letter also serves as a crucial reminder to exercise discernment in leadership, rejecting those who, like Diotrephes, are driven by pride and a desire for control. Instead, we are called to imitate the humble and faithful example of those like Gaius and Demetrius, whose lives are characterized by love, truth, and a commitment to serving others. This epistle challenges us to examine our own lives and ensure that our actions align with the truth of the gospel we profess.