Romans 12
20 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.
21 Be not overcome of evil, but overcome evil with good.
Proverbs 25
21 If thine enemy be hungry, give him bread to eat; and if he be thirsty, give him water to drink:
22 For thou shalt heap coals of fire upon his head, and the Lord shall reward thee.
Commentators differ in their interpretation of the words, “For so you will heap coals of fire on his head”. If your enemy harms you and you deal well with him in return, he will find it surprising and unexpected. That will be like burning coals of fire on his conscience and the Lord will also reward you.
Example: There were two men who were neighbours; the one a Christian and the other a heathen. The heathen’s cow regularly grazed in his neighbour’s vegetable garden and destroyed much of his vegetables. Each time the Christian would return the cow and start his vegetable garden from scratch. Eventually he felt that he had had enough. He even thought of poisoning the cow, but then he prayed and asked God for wisdom. So he took back the cow and said to his neighbour, “Here is your cow that has been grazing in my vegetable garden. If it should happen again, then …”, and he stopped. His neighbour indignantly answered, “then what?”. But he kept quiet and his neighbour pressed him and raised his voice, “tell me, what will you do then, ugh?”. At last he answered quietly, “then I will bring it back to you again.” This soft answer pricked the heathen’s conscience and the cow never roamed into the Christian’s yard again.
In the same way Elijah also treated his king with great respect, although Ahab was so evil and only did him harm. After the prophets of Baal were killed, Elijah prayed for rain. When God answered him, he sent word to the king to prepare his chariot and go into the city lest the rain should overtake him. And Elijah himself ran in front of the king’s chariot to his honour, as we read in 1Sam 8:10, 11.
Elijah did good to king Ahab and his wicked wife Jezebel, but they hardened themselves in their wickedness and God eventually destroyed them.