Whoever says he is in the light and hates his brother is still in darkness. (1 John 2:9)
What does this mean? Can we hate our brother if we’re saved? I thought our lives were supposed to be characterized by love?
Yes, that is true, but the sin nature is still inside us, crouching at the door and waiting to leap. Since our lives are supposed to be characterized by love, our lives should reflect the highest and best love: love for Jesus and love for our brethren. Sadly, it doesn’t always happen that way.
Else, as Paul put rhetorically but actually to the Corinthians,
For I fear that perhaps when I come I may find you not as I wish, and that you may find me not as you wish—that perhaps there may be quarreling, jealousy, anger, hostility, slander, gossip, conceit, and disorder. (1 Corinthians 12:20)
Else, why would Jesus and Paul admonish those who take the Lord’s Supper to reconcile with brethren or examine one’s self before doing so, in order that taking the Supper would not be done in an unworthy manner? (1 Corinthians 11: 27; Matthew 5:23-24).
Jamieson-Fausset-Brown Bible Commentary puts it simply
his brother—his neighbor, and especially those of the Christian brotherhood. The very title “brother” is a reason why love should be exercised.
The command to love one another is an old one, says John in 1 John 2, but with a new twist. John uses the analogy of light and dark throughout his epistle. The command to love is nothing new, but it is a specific and foremost spiritual test to determine who is in the faith and who is not. John MacArthur here in his sermon Live Life By a New Love:
If you hate your brother, if you hate others, if you hate those in the Kingdom, if you hate anyone essentially, if you don’t see people the way God sees them then He’s not in control of your heart. Love proves everything when connected to sound doctrine.
But in 1 Corinthians 15, if you don’t have love it’s all noise, it’s all noise. So the practicality of it is, if you’re a true Christian it’s going to show up in your love, not perfect love, love is not going to be the perfection of your life but it will be the direction of it. You’re going to have a heart of love for those around you, not a heart of hatred. You’re going to want to serve those around you, not demand from them. You’re going to want to help those around you, not harm them. You’re going to want to come to the aid of those around you, to lift them up not to step on them. And particularly is that true among believers. If you don’t have a love to be with God’s people, it’s a clear evidence that you’re in the darkness no matter what you claim.
The Light is warm and bright, it’s where love is.