What does 1 John 4:2 mean?

The first way to determine whether a teacher is from God or not is given here. If a person confesses Jesus is the Christ, and that He came fully human into the world, this is a sign the teacher's spirit is godly. The context of this statement is important, however. This is not meant to be the one and only way Christians are to gauge spiritual teachings. A major concern for John's readers were those who denied that Jesus was fully human. Throughout history, there have been other false teachers who have accepted the humanity of Christ, yet deny other important aspects of the gospel.

First Corinthians chapter 15 gives another example of a false teaching which needs to be discarded: rejecting Christ's literal, bodily resurrection. John's statement here is true, but it is not presented as the only test for spiritual truth. There are additional concerns discerning believers must address in dealing with whether someone is a false prophet. Some of those other tests are included in verses 3 through 6.