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.
NIV
[And] not be like Cain who [took his nature and got his motivation] from the evil one and slew his brother. And why did he slay him? Because his deeds (activities, works) were wicked and malicious and his brother's were righteous (virtuous).
AMP
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.
KJV
Adam made love to his wife again, and she gave birth to a son and named him Seth, saying, "God has granted me another child in place of Abel, since Cain killed him."
NIV
And Adam's wife again became pregnant, and she bore a son and called his name Seth. For God, she said, has appointed for me another child instead of Abel, for Cain slew him.
AMP
And Adam knew his wife again; and she bare a son, and called his name Seth: For God, said she, hath appointed me another seed instead of Abel, whom Cain slew.
KJV
But the LORD said to him, "Not so; anyone who kills Cain will suffer vengeance seven times over." Then the LORD put a mark on Cain so that no one who found him would kill him.
NIV
And the Lord said to him, Therefore, if anyone kills Cain, vengeance shall be taken on him sevenfold. And the Lord set a mark or sign upon Cain, lest anyone finding him should kill him.
AMP
And the LORD said unto him, Therefore whosoever slayeth Cain, vengeance shall be taken on him sevenfold. And the LORD set a mark upon Cain, lest any finding him should kill him.
KJV