Romans 12:20

Therefore if your enemy hungers, feed him. If he thirsts, give him drink. For in so doing you shall heap coals of fire on his head.

Proverbs 25:21-22

If your enemy is hungry, give him bread to eat; and if he is thirsty, give him water to drink,

Matthew 5:44

But I say to you, Love your enemies, bless those who curse you, do good to those who hate you, and pray for those who despitefully use you and persecute you,

Luke 6:27

But I say to you who hear: Love your enemies, do good to those who hate you,

Exodus 23:4-5

If you meet your enemy's ox or his ass going astray, you shall surely bring it back to him again.

1 Samuel 24:16-19

And it happened when David had made an end of speaking these words to Saul, Saul said, Is this your voice, my son David? And Saul lifted up his voice and wept.

1 Samuel 26:21

And Saul said, I have sinned. Return, my son David, for I will never do you harm any more, because my life was precious in your eyes this day. Behold, I have acted foolishly, and have greatly erred.

2 Kings 6:22

And he answered, You shall not strike them. Would you strike those whom you have taken captive with your sword and with your bow? Set bread and water before them so that they may eat and drink, and go to their master.

Psalm 120:4

Sharp arrows of the mighty, with coals of broom.

Psalm 140:10

Let burning coals fall on them; let them be cast into the fire; into deep pits, so that they do not rise up again.

Song of Songs 8:6-7

Set me as a seal on Your heart, as a seal on Your arm; for love is strong as death. Jealousy is cruel as the grave; its flames are flames of fire, a flame of Jehovah.

Treasury of Scripture Knowledge

Summary

Therefore if thine enemy hunger, feed him; if he thirst, give him drink: for in so doing thou shalt heap coals of fire on his head.

Bible References

If thine

Exodus 23:4
If you meet your enemy's ox or his ass going astray, you shall surely bring it back to him again.
1 Samuel 24:16
And it happened when David had made an end of speaking these words to Saul, Saul said, Is this your voice, my son David? And Saul lifted up his voice and wept.
1 Samuel 26:21
And Saul said, I have sinned. Return, my son David, for I will never do you harm any more, because my life was precious in your eyes this day. Behold, I have acted foolishly, and have greatly erred.
Proverbs 25:21
If your enemy is hungry, give him bread to eat; and if he is thirsty, give him water to drink,
Matthew 5:44
But I say to you, Love your enemies, bless those who curse you, do good to those who hate you, and pray for those who despitefully use you and persecute you,

Coals

Psalm 120:4
Sharp arrows of the mighty, with coals of broom.
Psalm 140:10
Let burning coals fall on them; let them be cast into the fire; into deep pits, so that they do not rise up again.
Song of Songs 8:6
Set me as a seal on Your heart, as a seal on Your arm; for love is strong as death. Jealousy is cruel as the grave; its flames are flames of fire, a flame of Jehovah.

General references

Exodus 23:4
If you meet your enemy's ox or his ass going astray, you shall surely bring it back to him again.
Proverbs 3:30
Do not strive with a man without cause, if he has done you no harm.
Proverbs 25:21
If your enemy is hungry, give him bread to eat; and if he is thirsty, give him water to drink,
Matthew 5:42
Give to him who asks of you, and you shall not turn away from him who would borrow from you.