Last week I pointed out that God’s call to love one another started in Genesis not with Jesus. The apostle John wrote that this message was “from the beginning” and illustrated how not to do it via Cain’s example. “We should not be like Cain, who was of the evil one and murdered his brother” (1 John 3:12a). Getting mad and murdering is an old story.

Cain killed his own brother. The second half of verse twelve asks and answers: “And why did he murder him? Because his own deeds were evil and his brother’s righteous.” More is happening than bad guy versus good guy. Cain’s evil deeds came from Cain’s evil heart, but not because evil is simply absurd and unpredictable. Sometimes sin is senseless, but more often it has an explanation.

John is not making an argument based on the absurdity of Cain’s murder. “He was of the evil one, so of course he would kill.” John answers the Why? question with a reason, a “because.” Cain’s deeds were evil when he looked at Abel’s. Cain’s hatred was driven by jealousy not by stupidity. Cain wanted Abel’s blessing from God but without the hassle of Abel’s sacrifice to God.

Envy-killing is serious business. John is warning all his readers, meaning that he’s warning the Christians. Watch out especially for envy, even envy of believers who are blessed by God. “I wish I could be [adjective] like him.” “I wish I could have [noun] like her” are dangerous desires. They take the life out of fellowship, unity, gratitude, and joy, even if they don’t put a brother in his grave.

Do not let roots of bitterness grow up into a harvest of jealousy, hatred, and death.