Dear children, do not let anyone lead you astray. The one who does what is right is righteous, just as he is righteous. The one who does what is sinful is of the devil, because the devil has been sinning from the beginning. The reason the Son of God appeared was to destroy the devil’s work. No one who is born of God will continue to sin, because God’s seed remains in them; they cannot go on sinning, because they have been born of God. This is how we know who the children of God are and who the children of the devil are: Anyone who does not do what is right is not God’s child, nor is anyone who does not love their brother and sister.
1 John 3:7-10
This is an interesting passage; don’t let anyone lead you astray… There are many, who would do so, and they may try by appealing to our pride or vanity, they might appeal to greed or lust, they might even appeal to our intellect with attractive arguments or curious reasoning, but have you ever asked yourself why they would bother?
John gives the reason in this passage: They are sinful, of the devil and doing the devil’s work, because the devil has been in rebellion against God since the beginning and is looking for allies… or at least to separate us from Christ. It is really important that we get this point. It is the work of the devil to separate us from Christ, because in Christ we are part of His work, and His work is to destroy the works of the devil. Actually, this is so simple we might miss it! In Christ, we are a threat, so there will be opposition.
Within this context, John speaks of doing what is right as opposed to doing what is sinful, and in this context doing what is right means following Jesus Christ, and doing what is sinful means not following Christ and trying to lead His followers astray. So far, this is very straight forward, and then John throws us a curve at the end, a curve that leads us to the next section. Doing right means that we love one another; doing wrong means that we don’t.
Simple answer: If we do not love one another as He loved us, then we can’t possibly be following Jesus Christ, because loving one another is where He is leading!