I John Chapter Three
I John 4:17 explains that God’s election (love) is “perfected with us, so that we have confidence in the day of judgment, because as He is so also are we in the world.”
Legal justification is the only way the elect can be as He is in the world. (Check out your commentaries on this: even commentators who deny that the “fine linen” of the saints (John’s Revelation) is by imputation, even most of these commentators agree that I John 4 is about God’s love resulting in legal union with Christ and His obedience.) .
I John 3 is about the difference between a Nicodemus and a prodigal publican, about the difference between a religious Cain and a religious Abel. Think of the context. This is not about Abel having a better inside than another person! The religion of Cain is nothing but evil deeds.
The reason Cain hated Abel was that Cain wanted to glory in/ rejoice in (Phil 3:3) the deeds done by his false god IN himself. Cain refused to put to death (not count) those deeds (Rom 8:13) but instead wanted to worship a god who would accept Cain’s credit for producing life in Cain.
To pass over from death to life is to be put into the new man, to be given a new legal state, in which one’s confidence is not in what God does in you but rather in what God has done in Christ outside you. Only in this way can we be in the world as Christ was in the world.
The Cains of this world are ready for a self-examination and contrast in terms of their morality. They are Pharisees who contrast well with alcoholics and people who watch the Simpsons on TV. But these Cains “do not practice righteousness” (I John 3;10). These Cains will not come to the light, because they love darkness and the light of the gospel (God forgives sinners by Christ’s death) keeps telling these Cains that their deeds are evil. All their deeds, both moral and religious. (John 3:19).
These Cains want to thank their god not only for the deeds they do but also for putting “life in their souls”. But the true God won’t accept their thanks. And those like Abel who worship in truth won’t fellowship with that self-righteous religion. That’s why Cain hated Abel.