Romans 12:20

But if one who has hate for you is in need of food or of drink, give it to him, for in so doing you will put coals of fire on his head.

Proverbs 25:21-22

If your hater is in need of food, give him bread; and if he is in need of drink, give him water:

Matthew 5:44

But I say to you, Have love for those who are against you, and make prayer for those who are cruel to you;

Luke 6:27

But I say to you who give ear to me, Have love for those who are against you, do good to those who have hate for you,

Exodus 23:4-5

If you come across the ox or the ass of one who is no friend to you wandering from its way, you are to take it back to him

1 Samuel 24:16-19

Now when David had said these words to Saul, Saul said, Is this your voice, David, my son? And Saul was overcome with weeping.

1 Samuel 26:21

Then Saul said, I have done wrong: come back to me, David my son: I will do you no more wrong, because my life was dear to you today truly, I have been foolish and my error is very great.

2 Kings 6:22

But he said in answer, You are not to put them to death; have you any right to put to death those whom you have not taken prisoner with your sword and your bow? put bread and water before them, so that they may have food and drink and go to their master.

Psalm 140:10

Let burning flames come down on them: let them be put into the fire, and into deep waters, so that they may not get up again.

Song of Songs 8:6-7

Put me as a sign on your heart, as a sign on your arm; love is strong as death, and wrath bitter as the underworld: its coals are coals of fire; violent are its flames.

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 come across the ox or the ass of one who is no friend to you wandering from its way, you are to take it back to him
1 Samuel 24:16
Now when David had said these words to Saul, Saul said, Is this your voice, David, my son? And Saul was overcome with weeping.
1 Samuel 26:21
Then Saul said, I have done wrong: come back to me, David my son: I will do you no more wrong, because my life was dear to you today truly, I have been foolish and my error is very great.
Proverbs 25:21
If your hater is in need of food, give him bread; and if he is in need of drink, give him water:
Matthew 5:44
But I say to you, Have love for those who are against you, and make prayer for those who are cruel to you;

Coals

Psalm 140:10
Let burning flames come down on them: let them be put into the fire, and into deep waters, so that they may not get up again.
Song of Songs 8:6
Put me as a sign on your heart, as a sign on your arm; love is strong as death, and wrath bitter as the underworld: its coals are coals of fire; violent are its flames.

General references

Exodus 23:4
If you come across the ox or the ass of one who is no friend to you wandering from its way, you are to take it back to him
Proverbs 3:30
Do not take up a cause at law against a man for nothing, if he has done you no wrong.
Proverbs 25:21
If your hater is in need of food, give him bread; and if he is in need of drink, give him water:
Matthew 5:42
Give to him who comes with a request, and keep not your property from him who would for a time make use of it.

Basic English, produced by Mr C. K. Ogden of the Orthological Institute - public domain