That the injunction to christian brotherly love is here meant by the new command, is implied in the succeeding words, which indicate the close connection between that assumed state of the church, that living in the light, and the exercise of brotherly love; as, in like manner, by darkness is designated the opposite of this love, viz. selfishness, which excludes love, which begets hate, -- the characteristic mark of the life of darkness. "He that saith he is in the light, and hateth his brother, is in darkness even until now."

With John, as will readily be perceived, the expressions "being in the light," being in fellowship with Christ as the true light, being enlightened by him, and being a christian, all mean the same thing; just as, on the other hand, "being in darkness," being shut out from Christ the true light, and belonging to the ungodly world, all have the same meaning. He who claims to be a christian, and hates him whom he should love as a brother, proves thereby, that however long he may have professed Christianity, he is in truth as far from it as ever. That spirit of hatred towards his brother is a sure token, that he has never yet become a partaker of the divine light; that the darkness of the world, the same spirit which governs the God-estranged world, still reigns in him. Not inwardly, but only outwardly, seemingly, has he renounced the world. The light of Christ has not yet risen in his soul; for this cannot co-exist with such a temper of mind.

Now it is worthy of note, that John makes but this one distinction: He that hateth his brother, and he that loveth his brother. He recognizes no intermediate state, which, while it is indeed far from self-sacrificing love, is far also from hatred of the brethren. This is John's peculiar manner; viz. without regarding intermediate steps and gradations in opposite moral states, to seize upon the radical point of difference, and thus contrast them in their essential nature and principle. And with full reason. For either love, to the exclusion of the selfish element, is the animating principle; or self is made the centre of all, and selfishness governs. Now in this selfishness, the opposite of brotherly love, inheres the tendency which, when consistently carried out, allows place to nothing that interferes with self-interest, and regards every one who comes in conflict therewith as an enemy, to be removed out of the way. Accordingly, in these opposite dispositions, viewed strictly with reference to their radical elements, we find only Love to the brethren, or Hatred of the brethren; love, which is ready for every sacrifice, or selfishness, which may also pass into hate. So Christ recognizes but two distinctions, -- serving God, and serving the world.