1 John 2:9

He who says he is in the light and yet hates his brother, is in the darkness till now.

1 John 2:11

But he who hates his brother, is in the darkness, and walks in that darkness, and does not know whither he goes; because the darkness has blinded his eyes.

1 John 3:12-15

Not being of the wicked one, as Cain was, who slew his brother. And on account of what, did he slay him? Because his own works were wicked, and his brother's righteous.

2 John 1:10-11

If any one come to you, and bring not this doctrine; receive him not into your house, nor wish him success:

Treasury of Scripture Knowledge

Summary

Thou shalt not hate thy brother in thine heart: thou shalt in any wise rebuke thy neighbour, and not suffer sin upon him.

And not suffer sin upon him

Bible References

Hate

1 John 2:9
He who says he is in the light and yet hates his brother, is in the darkness till now.
1 John 3:12
Not being of the wicked one, as Cain was, who slew his brother. And on account of what, did he slay him? Because his own works were wicked, and his brother's righteous.

And not suffer sin upon him

2 John 1:10
If any one come to you, and bring not this doctrine; receive him not into your house, nor wish him success: