1 John 3:12
ESV
We should not be like Cain, who was of the evil one and murdered his brother. And why did he murder him? Because his own deeds were evil and his brother 's righteous.
NIV
Do not be like Cain, who belonged to the evil one and murdered his brother. And why did he murder him? Because his own actions were evil and his brother’s were righteous.
NASB
not as Cain, who was of the evil one and murdered his brother. And for what reason did he murder him? Because his own deeds were evil, but his brother’s were righteous.
CSB
unlike Cain, who was of the evil one and murdered his brother. And why did he murder him? Because his deeds were evil, and his brother’s were righteous.
NLT
We must not be like Cain, who belonged to the evil one and killed his brother. And why did he kill him? Because Cain had been doing what was evil, and his brother had been doing what was righteous.
KJV
Not as Cain, who was of that wicked one, and slew his brother. And wherefore slew he him? Because his own works were evil, and his brother's righteous.
NKJV
not as Cain who was of the wicked one and murdered his brother. And why did he murder him? Because his works were evil and his brother’s righteous.
What does 1 John 3:12 mean?
In contrast with loving one another in verse 11, John brings up the example of the first murderer, Cain. Cain recognized God (Genesis 4), but did not follow Him. Instead, Cain showed that he did not love God by killing his brother. Hatred for one's brother—spiritually speaking—was already condemned as Satanic in 1 John 2:9. There is no sin which a Christian is not somehow capable of, but those who persist in "walking in darkness" cannot reasonably be considered saved.This verse also asks and answers the question of why Cain killed his brother: jealous resentment, since Abel's offerings were more acceptable than Cain's. Jealousy and hatred towards one's brothers and sisters is "of the evil one." Cain's offering was evil in some way, likely because he did not offer his best before the Lord. Abel's offering was considered righteous. John uses this contrast to show the difference between attitudes motivated by God, and those motivated by Satan. Hatred for the good that others do is absolutely evil, and a sign of someone lacking fellowship with Christ.