If your enemy is hungry, give him food to eat; if he is thirsty, give him water to drink. In doing this, you will heap burning coals on his head, and the Lord will reward you.- Proverbs 25:21-22
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Phoebe and Jane used to be best of friends while growing up in the same neighborhood. They were both born into humble families and they did everything together, went to the same school, at times, either of them could pass the night in the other person's house. They were that close. Children are used to projecting into the future with the perception that life is a straight line and it would just go the same way you think it would.
A child would often talk about when he would complete tertiary institution, when and where his/her (first) job (of course, the dream job) would be, when to get married, number of kids, how wealthy he would be, and so on. It was not different for Phoebe and Jane. They planned the future to the extent that they made a promise to one another that "the first person to become wealthy in life will lift the other." The both were so confident that the love they had for one another was eternal.
Thirty two years down the line, life pursuits had separated the two girls in distance. Jane has become so successful in her career, gotten married to a wealthy man, and has a beautiful family. Phoebe on the other hand is contented with her average lifestyle. At least her family has enough to cater for their needs, but nothing flamboyant.
Jane would often remember her childhood promise made to her friend, but brush it off, saying "we were young and stupid. I'm sure if she was in my shoes, she'll do same." Just so she can settle the scores and prove to her friend that she would treat her the same way, Jane takes a trip to Phoebe's house, far away in another city, pretending to be poor and in need of help.
It is with a mix of joy and pity that Phoebe welcomes her old friend, who narrates that pseudo news of how her family lost everything, how her children now stay with her pastor, how hungry she has been, and even is at the moment. Her expectation of course is that Phoebe will treat her with disgust, judging her for her negligence when she was enjoying the riches.
On the contrary, Phoebe welcomes her joyfully, gets her a change of clothes and convinces Nelson, her husband to help set her friend up with the little connections he has, and some funds to start up. Astonished at the way she is received and cared for, Jane reminds her friend of how unworthy she is to be helped in such a way, as she forgot and neglected her when things were rosy. Phoebe however promises that it is okay, that is bygone, and it is still her responsibility to fulfill that part of her promise in whatever capacity she can.
The show of love and affection stuns Jane that she decides to come clean, explaining to Phoebe that her intention is to come prove to her that she would treat her the same way she did. This treatment becomes a turning point for both friends as Jane, in appreciation of Phoebe and her family's love, fulfills her part of the promise by investing immensely in Nelson and Phoebe's joint business.
This story is that of a woman heaping coals of fire upon her friend. "Coals of fire" might likely be interpreted as destruction or calamity, but maybe not quite. Coals of fire in this context is a huge load of guilt, shame and debtor-mentality, especially when shown to an enemy, or someone who has gravely hurt you in times past. The bible urges us not to reciprocate evil with the same.
Do not repay evil with evil or insult with insult. On the contrary, repay evil with blessing, because to this you were called so that you may inherit a blessing.- 1 Peter 3:9
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Coals of fire upon the enemy is not a call for destruction or pain, or calamity, but a call to repentance, extending salvation to those who may be lost in darkness. it is a call to a better relationship with humanity and divinity, an invitation to the light.