The elder introduces himself again. This time, he's writing to Gaius, whom he calls "beloved" and says a quick prayer for.
He's super thankful that Gaius has opened up his house to make room for the elder's friends who are in town. Gaius's guest rooms must be pretty nice.
The friends of the elder have told him all about how awesome and loving and holy Gaius is. The elder is pretty psyched because it's clear that Gaius is still faithful to him and the community.
The elder explains that these friends are about to set out on a missionary journey. Everyone in the church should be supporting them because they're about to do something good: spread the word of God.
Gaius is way better than some people. Namely, Diotrephes.
That guy refuses to recognize the authority of the elder, and he's been turning away the elder's friends. Strike one and two, right there.
The elder tells Gaius not to follow in Diotrephes footsteps because he's doing evil and is clearly not godly. Burn.
Then he mentions Demetrius, a missionary to whom people keep giving glowing reviews and who the elder knows is living in the truth of God.
The elder finishes this letter in the same way as the last one. He says that he has more stuff to tell Gaius, but that it'll have to wait until they see each other in person. Until then, tell the friends that the elder says hey. Hey!