Summary: 1) Assurance of being in the truth (vv. 19–20), 2) Give confidence that prayer will be answered (vv. 21–22), and 3) Assure the believer of union with Christ (vv. 23–24).
Have you ever been praying and suddenly your conscience says something like this to you: “Look at you! Who do you think you are to come before God and ask anything from him! Why just this week you did things and said things that would disqualify you from ever receiving anything from God. Don’t you remember that attitude you had yesterday? Don’t you remember how you got angry with your wife for no reason last week? What about that unclean thought that passed through your mind three days ago? You passed someone broken down on the road and could have stopped to help, but you didn’t. You’re sure not much of a Christian, are you? What right do you have now to come to God and ask him for anything?” Thoughts such as these can shut down your prayer time in a New York minute. It’s hard to pray when you don’t have assurance and confidence that God welcomes you and is willing to hear your prayers.
John has something vital to say about this situation in 1 John 3:19–24. The center of this passage is John’s appeal in verse 23: we should believe in Jesus and love one another. This appeal is flanked on both sides with a motivational basis. Verses 19–22 provide the first motivation: when our conscience condemns us, God is greater than our conscience, giving us assurance that we will receive what we ask from him in prayer. Verse 24 constitutes the second motivation: we can be assured that God lives in us and we abide in him. The topic of this paragraph is confidence. Notice John’s use of words like “know,” “reassure,” and “confidence.” Confidence is based on the fact that we have believed in Jesus and are thus in the family of God and that, as obedient children in the family, we love others in the family. Since we are in the family and since we love others in the family, we can come to our Father with our prayer requests with confident assurance that he will hear us (Allen, D. L. (2013). 1–3 John: Fellowship in God’s Family. (R. K. Hughes, Ed.) (pp. 163–164). Wheaton, IL: Crossway.).
In verses 19–24 John set forth the assurances that will arise in the heart of the believer from the practice of love; they are the fruit of love. The practice of love will produce 1) Assurance of being in the truth (vv. 19–20), 2) Give confidence that prayer will be answered (vv. 21–22), and 3) Assure the believer of union with Christ (vv. 23–24).
1) The assurance of being in the truth (vv. 19–20)
1 John 3:19–20 19 By this we shall know that we are of the truth and reassure our heart before him; 20 for whenever our heart condemns us, God is greater than our heart, and he knows everything. (ESV)
Every human being is born with the law of God written in the heart and with a conscience to accuse or excuse (Rom. 2:14–15). This means every person has some degree of self-knowledge and some innate ability to recognize right and wrong. Because of this fact, the apostle John understood that at times true believers can struggle with their assurance. Some of the Apostle John’s readers may have been so overwhelmed by the memory of their past sins and awareness of present ones that they found the thought of God’s forgiveness nearly impossible to accept. Their overactive consciences, beleaguering them with their own shortcomings, perhaps made it difficult for them to have a settled confidence in their right standing before God. So John wrote to encourage those believers and enable them to accurately evaluate their own spiritual condition. In so doing, he sought to solidify their conviction, rightly inform their conscience, and strengthen their assurance with a true understanding of their transformation and its evidences. John is not thinking of our continual assurance that we belong to God, but rather of the coming of a crisis of belief when we want to know whether we belong to God. In such a situation we are to examine ourselves to see whether we are keeping the command given to us by God (Marshall, I. H. (1978). The Epistles of John (p. 197). Grand Rapids, MI: Wm. B. Eerdmans Publishing Co.).
In verse 19, by this, most naturally refers back to verse 18’s admonition for brotherly love. We shall/will know brotherly love. We shall/will know translates a form of the common Greek verb ginōskō, which means “to know,” “to learn,” “to find out,” or “to realize.” John’s use of the future tense indicates that what his readers would eventually grasp was not something intuitive or indefinite, but a promise based on an existing reality. When believers know they have sincere love for one another, they can be certain that they are of the truth (the phrase literally reads, “out of the truth we exist”). Only those who have been genuinely converted through the supernatural work of God possess the sacrificial love that John describes in verses 14–18, which issues in the submissive obedience that John delineates in verses 4–12. The self-sacrificial, active love previously described offers evidence that one is “of the truth.” Truth can only characterize the behavior of those whose very character originates in the truth, so that it is by our loving others ‘in truth’ that we know that we ourselves belong to it” [are of the truth] (Akin, D. L. (2001). 1, 2, 3 John (Vol. 38, p. 163). Nashville: Broadman & Holman Publishers.)