Changing the Gospel message to be more palatable for themselves.
John writes because of this distortion and because he loves these people and their joy so much.
The Message is the Word of Life
I am writing to you about the word of life.
Remember John is writing to a second generation of believers who are being confused by these deceivers and he wants to add strength to what he is saying.
I proclaim what I have seen with my own eyes and touched with my hands.
Fellowship without love is not fellowship
The term ‘fellowship’ (koinōnia) is only used four times in the book of 1 John (and not at all in 2 John, 3 John, or the Forth Gospel)! It is used in verses 3, 6, and 7.
This means this was a term used by those who John is writing against.
Fellowship with God (and John) is a partnership in the work of proclamation.