If anyone claims to be in the light but hates his brother, he is still in the darkness.
9 He that saith he is in the light He pursues the same metaphor. He said that love is the only true rule according to which our life is to be formed; he said that this rule or law is presented to us in the Gospel; he said, lastly, that it is there as the meridian light, which ought to be continually looked on.
The seventh verse may be supposed either to look backward to what immediately preceded (and then it is walking as Christ walked that is here represented as no new, but an old commandment; it is that which the apostles would certainly inculcate wherever they brought Christ's gospel), or to look forward to what the apostle is now going to recommend, and that is the law...
Commenting on 1 John 2:7-11
He that saith he is in the light,.... Is in Christ the light, or has the true knowledge of the light of the Gospel, or is illuminated by the Spirit of God; for persons may profess to be enlightened ones, and not be so: wherefore the apostle does not say, he that is in the light, but he that says he is, and hateth his...