In the previous section John wrote about the certainty that we have been born (again) as children of God (2:29-3:10). In this section the fourth basis for assurance is the love that we have for the family: "We know that we have passed from death to life because we love one another" (1 John 3:14). Those who have been raised to faith in a Christian home do not know the sudden inrush of love for our brothers and sisters that surprises those who are converted later in life. As I remember this initial experience it still astonishes me after fifty-four years.
As time goes on we need reminders to be practical about our love for our new family. "Little children, let us love, not in word or speech, but in truth and action. And by this we will know that we are from the truth and will reassure our hearts before him" (3:18). Which means that each new experience of that family love adds to the assurance that John wants us to have. In the next section (3:24b-4:14) we will see that this unexpected love is the first evidence of the work of the Holy Spirit in our lives.
3:12 There was a murder in the very first human family when one son killed his brother (Genesis 4:8). The reason for that murder was that Abel's offering was accepted by God, but Cain's offering was not acceptable. When Cain was angry, God explained that his brother's offering was an expression of his right attitude, but Cain's offering was flawed by his sinful behavior (Genesis 4:5-7). Those who only pretend to be religious inevitably hate those who love God.
3:13 This means we should not be surprised if the world (and that includes the Pharisees and Sadducees of Jesus' day) hates us.
3:14 An evidence that we have passed from spiritual death to God's kind of life (Ephesians 2:1-5) is that we love our brothers and sisters in God's family. If however we are filled with jealousy (as was Cain) and hatred, it is a sure sign we are still spiritually dead.
3:15 John is still referring to Cain's murder of his brother Abel. Jesus pointed out three kinds of murder without actually killing the person. Murderous anger, writing a person off with raca, and treating others as complete idiots, whose opinion does not count (Matthew 5:21-22).
3:16 There are many facets of the Messiah's love when he died on the cross. But one was his willingness to die for his adopted brothers and sisters. He could have called in twelve legions of angels to snatch him away from crucifixion (Matthew 26:53), but if he had done this his disciples would have been abandoned and scattered. It was his willingness to die, and the resurrection they saw and experienced, that empowered them to continue as a brotherhood to include people of all nations. It is this quality of love for our fellow servants that defines for us what love is.
3:17 This is not a sentimental impractical love, but a genuine concern to act when others of the family are in need. These days many claim a love for all people, and they easily get moved by human needs in distant places. Sending $10 in answer to an emotional appeal may salve one's conscience, but in the long run it does not solve the underlying problem. The quickest way to meet the vastness of human need is to establish welcoming and loving families of God in every place. This is the leaven that can change the world.
3:18 Love is not expressed by mere talk, but by action and the truth of the good news (for the importance of truth see 1:6, 2:4).
3:19 And it is when the love of God works in and through us that we know that we have the assurance we need (see the introduction about certainty and assurance).
3:20 Satan want us to be riddled with guilt and self-condemnation, usually by making us wonder what others think about us. But it is important to remember that God knows us through and through.
3:21 So we need to go beyond our own inadequacy to be bold in our assurance of being children of God, and our love for our brothers and sisters.
3:22 This obedience of love (as in 2:3-6) enables us to pray with confidence. If we continue to be angry with a brother or sister, it is very hard to pray.
3:23 The commandment is very simple, to believe in the Messiah Son of God, and love one another.
3:24a And this is what obedience means (as in the section on obedience, 2:3-2:17). As we respond to the Messiah and love our brothers and sisters, we experience what Jesus said about abiding in the Vine and he as the Vine abiding in us (John 15:1-5).