This study comes from 1 John 3:19-4:6
3:19-24The Assurance of the Holy Spirit
19 This is how we know that we belong to the truth and how we set our hearts at rest in his presence: 20 If our hearts condemn us, we know that God is greater than our hearts, and he knows everything. 21 Dear friends, if our hearts do not condemn us, we have confidence before God 22 and receive from him anything we ask, because we keep his commands and do what pleases him. 23 And this is his command: to believe in the name of his Son, Jesus Christ, and to love one another as he commanded us. 24 The one who keeps God’s commands lives in him, and he in them. And this is how we know that he lives in us: We know it by the Spirit he gave us.
We agreed that there are times in every Christian's life, when faced with our own failures, we ask questions, like “Am I really saved?” “Do I have eternal life?” But note we are living a Christian life, despite our failures. The very fact that we raise such questions shows the work of the Spirit in our lives. No one is saved by their own works, but by God's grace alone. This is what we are relying on, Jesus' sacrifice on the cross. So we are not to feel condemned (3:20) by our hearts when we fall down. God is greater than our hearts and has provided an atoning sacrifice (4:10) that we can rely on to cover our multitude of sins. So we can then approach God in confidence (3:21).
“ to believe in the name of his Son, Jesus Christ” (3:22) is not simply to believe he exists; (See James 2:19). It is to trust in the character, nature (human and divine), words, promises, resurrection, purposes, plans and power of Jesus Christ.
4:1-6 Test the spirits
4:1 Dear friends, do not believe every spirit, but test the spirits to see whether they are from God, because many false prophets have gone out into the world. 2 This is how you can recognize the Spirit of God: Every spirit that acknowledges that Jesus Christ has come in the flesh is from God, 3 but every spirit that does not acknowledge Jesus is not from God. This is the spirit of the antichrist, which you have heard is coming and even now is already in the world.
John's readers were already encountering false prophets in the form of the Gnostics who claimed to know God. How were they to discern who was telling the truth? Here is the answer. This was the test, acknowledging that the divine Christ came in human flesh to save us. (The Gnostics would never admit that!) And this is also the crux of the Gospel message!
4 You, dear children, are from God and have overcome them, because the one who is in you is greater than the one who is in the world. 5 They are from the world and therefore speak from the viewpoint of the world, and the world listens to them. 6 We are from God, and whoever knows God listens to us; but whoever is not from God does not listen to us.This is how we recognize the Spirit of truth and the spirit of falsehood.
The true church has always overcome the false spirits by keeping faithful to the gospel. This is due to the work of the Holy Spirit, “the one who is greater …...” Note the pronouns: “You” (4:4) refers to the Church. “They” (4:5) refers to the false prophets. “We” (4:6) refers to the Apostles and the successive leaders who stayed true to the apostolic teaching.