John is one of the two letters in the New Testament that is anonymous. The other is Hebrews. The authorship of John is traditionally attributed to the apostle John, the same author as the gospel. It is written by someone who perceived himself to be an authority, a father figure if you will – someone who expected that his readers would listen to him because of his stature.
Important in our understanding of any book is context. The issue in the background of the 1st epistle of John is Gnosticism. A simplistic definition of Gnosticism for our purposes is a follows: Gnosticism is a philosophical religious perspective with the view that 1) matter is evil and the spirit is good 2) Knowledge (gnosis from the Greek word for knowledge) is revealed incrementally with the more spiritual being exposed to a more “secret” knowledge 3) for our purposes they would therefore deny that Christ was God in the flesh as the true God would not contaminate himself with matter which is evil. In particular John was probably combating a particular early form of Gnosticism known as Docetism. Docetism mainly denied the incarnation, buying into the idea that evil and matter were linked. Hence you can see the emphasis of John in rebutting this idea in the opening (1:1-3) and especially forcefully in 4:2-3.
John is also very clear in stating his purpose in writing: 1:3-4; 2:1; 2:26; 5:13. He wants his readers to have a vibrant horizontal and vertical fellowship; to have joy completed; to live in a holy manner apart from sin; to avoid deception; and to have assurance of eternal life.
Another notable feature with regard to 1 John is that it is the only book (plus one reference in 2 John) where the word “anti-Christ” appears (1 John 2:18, 22; 4:3 & 2 John 7).
Finally, let me make a structural observation (I don’t know where I got this, it is not original to me but is in my Bible margins and I know that I got it from another source…anyone who knows I would appreciate being able to cite it). The book seems to revolve around three “tests”
- The Moral Test (2:3-6; 2:28-3:10a)
- The Social Test (2:9-11; 3:10b-18; 4:7-12;
- The Doctrinal Test (2:18-27; 4:1-6)
- Combinations of the tests (3:22-24; 4:13-21; 5:1-5)