To begin with, we can say what it does not mean. John does not mean that obedience to God’s commandments is the condition for knowing God. Instead he means that obedience is the confirmation that a person has come to know God.
John uses the perfect tense when he refers to a person having come to know God, which indicates that there is a specific moment when a sinner comes into this relationship with him. A sinner may be aware of that moment of conversion because it was a vivid encounter or he may not be aware of it because it occurred during a prolonged exploration of the gospel message. Whenever that moment was, it was not the climax of a process of obedience to God’s law. Any sort of law-keeping that existed before that moment was self-righteousness. The way of entering this relationship is by faith in Christ, accompanied by repentance for our sins. But once this relationship has begun, it will be confirmed as genuine by the presence of obedience.
In addition, John is not saying that a true disciple keeps God’s commandments perfectly. He has stated in the previous verses that every Christian needs to confess sin and will do so throughout his life, and sin is basically a failure to keep God’s requirements. All Christians fail, therefore John is not describing a perfect keeping of God’s commands. Nor is John saying that a believer cannot backslide into a period of disobedience – such a decline is always possible, although it is important to realise that the proof that a person was a backslider is that he or she eventually repented of their sins.
Further, John is not describing a mere outward conformity to God’s rules. In one sense it is easy to have a moral lifestyle in which a person lives an outward life that looks like the kind of life that God requires. Those who were brought up within a church environment can have such a way of life and often it would be hard for radical outward change to take place. Nevertheless there is a radical inner change in the hearts and minds of all true converts. We will consider other aspects of Christian obedience tomorrow.