This third Epistle of John is a letter about three men. Their names are Gaius [GAY us], Diotrephes, and Demetrius.
Two of the men stand in sharp contrast to the other one. Let’s look at these two first.
I. GAIUS—the person to whom the epistle is addressed.
A. Shown evidence in his life of the Truth—how? By walking in it—vv. 3-4.
B. Shown love and concern for the brethren and for strangers--v. 5.
II. DEMETRIUS—possibly the pastor.
A. Well thought of by many.
B. Well thought of by the aged Apostle John.
These two men:
A. Pious examples to be imitated.
B. Personal lives that merit commendation.
On the other side there is DIOTREPHES:
A. “Loveth to have the preeminence” wants to be the top dog, the big cheese.
B. “Receiveth us not”—rejects proper God-ordained authority.
C. “Prating against us”—speaks evil against those over him in the Lord.
D. “Forbiddeth them that would”—wants to draw everyone in on his rebellious activities
Verse 11 is the Key Verse:
Beloved, follow not that which is evil”—Diotrephes and his rebellion
but that which is good”---the godly example of men like Demetrius and Gaius. "He that doeth good is of God: but he that doeth evil hath not seen God.”—the fruit of their lives proves the kind of person they are.
