Chapter three is the most troublesome part of the letter for many people, especially the first half. John’s declarations are bold, even harsh, and leave no room for mistakes. “Everyone who sins has neither seen him nor known him” (1 John 3:6). “Everyone who does not practice righteousness…is not of God” (1 John 3:10). However, as chapter two proved, the ideal is not always the real. John knew that his readers would continue to sin, but he did not want them to think that was to be shrugged off as “human nature.” No, those fathered by God are not bound by “human nature;” we have a divine nature that is at work in us. John insisted that God’s goal be our goal, even though we continue to fail miserably. Another consideration is the truth that, when we are remaining in Christ (see John 15:1-8), we will not sin, because the Holy Spirit never leads us to sin. Thus, John could legitimately write, “Everyone who remains in him does not sin” (1 John 3:6).
If the first half of the chapter is the negative side – what the Christian life should not include – the second half is the positive – what it should include, namely, love for our fellow Christians. Using Cain as his example, John wrote that hating a fellow believer (“brother”) is akin to murder. Again, this makes sense. Murder is wrong because people are made in God’s image (Genesis 9:6). Hate separates people, essentially throwing a believer – someone in Christ’s image – back to the world which hates him (1 John 3:13); it is spiritual homicide, something that cannot be done by someone who is actively living out God’s love. This includes shutting off help in time of need (1 John 3:17). Christian love must necessarily be more than a kind word, something already evident in John’s day.