1 John 3:11, 12, 23

For this is the message you heard from the beginning: We should love one another.

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.

And this is his command: to believe in the name of his Son, Jesus Christ, and to love one another as he commanded us.