Having identified all people as sinners, and having shown us that Jesus alone is the hope of sinners, John now presses home a self-test to help us see whether we are really trusting Jesus.
“By this we know that we have come to know him, if we keep his commandments. The one who says that he knows him but does not keep his commandments is a liar and the truth is not in him. But if one keeps his word, truly the love of God is completed in him.”
To know Jesus is to be a Christian. What should the Christian’s response be to Christ? They keep the Law of God.
This passage is not intended to send Christians into a dead panic. It is meant to give Christians — those who really do trust Jesus and him alone for salvation — good reason for assurance.
John has given us a way to test our attitude to God and his law. Are we still at war with God, or do we now trust him. Do we see the law of God as good, holy, just and spiritual, or do we still hate it? This test of attitude assures Christians that they really do know God.
The word translated in our bible as ‘keep’ has a variety of uses in God’s word.
It can mean to watch closely in a positive or negative sense. In John’s gospel (15:20), Jesus warned his disciples that, just as the religious leaders had watched closely, or kept (a record of), Jesus’ words in order to accuse him, these religious leaders would do the same to them.
The word ‘keep’ has been used in reference to guarding, such was the shepherds who kept their watch on the night Jesus was born, or the guards who were appointed to keep watch over Peter when Herod arrested him.
Again Jesus said to his disciples, ‘If you love me, you will keep my commandments.’
Now, the word ‘keep’ in itself does not imply perfect success in keeping anything. For example, the guards’ best efforts at keeping Peter in prison failed. But it does imply a purposeful attempt to keep the charge given.
More than this, it speak to the natural consequence of being a Christian.
- shepherds keep sheep
- prison guards keep prisoners
- religious leaders keep words
- Christians keep God’s law
By virtue of who they were, they all intended to keep their trust.
Both John and Jesus link this “keeping” to a right attitude toward God and his law.
John clearly indicates that Christians will fail in their purposeful efforts to keep the commandments of God. But, John and Jesus see the desire and the endeavour to keep God’s law as an indication that a person is a Christian.
Such a person will not have a relaxed attitude toward their sin. When people are brought to faith in Jesus Christ, they will aim to do what God requires. They will do this, not to be saved but because they already have been saved (Exodus 20:1).
They now love God and his son, Jesus Christ. The love of God was completed in them when they trusted Jesus (Jer. 31:33). These people will aim to keep God’s commandments because they know him and his law is written in their hearts. David said to God, “Oh how I love your law.”
If a person has a bad attitude toward God’s law, if that person thinks it an unnecessary imposition upon personal freedom, if a person is untroubled by failure to keep God’s law, there is a real danger that this person does not really trust Jesus Christ for salvation.
If a person with such a bad attitude were to say that “I know Jesus”, John says such a person is a liar.
The good news of Jesus is to bring people back to God. Jesus did this by his own good life, his death as our substitute, and his rising again from the dead.
When the Holy Spirit effectively applies this work of Christ to anyone, that person is justified before God. That person is also given new attitudes toward God and his law. Christians want to obey the one whom they love and trust. They will follow in his footsteps.
They are grieved when they fail, but they do not despair or give up. Why?
Because they “have an advocate with the Father, even Jesus Christ the righteous, who is himself the propitiation of our sin, and not only of ours but of the whole world.”