John writes to a beloved elder Gaius, praying that his physical health matches his spiritual health. He is overjoyed to hear about the obedience of fellow believers. He also expresses gratitude for Gaius' faithfulness towards truth and hospitality towards traveling teachers.
John rebukes a troublemaker named Diotrephes, who loves to be pre-eminent, rejects John's leadership, refuses to welcome traveling teachers, expels from church those who exhibit Christian hospitality. He warns this congregation.
3 John 1:11 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.Johns offers another example of godliness in Demetrius - who has a good testimony from all. John has much to say, but prefers to say it in person.
In closing, John exchanges greetings and pronounces blessings upon these fellow believers.