20 Like one who takes away a garment on a cold day,
or like vinegar poured on a wound,
is one who sings songs to a heavy heart.
21 If your enemy is hungry, give him food to eat;
if he is thirsty, give him water to drink.
22 In doing this, you will heap burning coals on his head,
and the Lord will reward you.
Good intentions are a nice thing to have, but without wisdom they are prone to backfire. Often in relationships, what we assume a person needs is neither needed nor wanted, and can sometimes only make things worse. This is particularly true with those in mourning. One person may need comfort, another may want help, and some need time alone to think things through. Instead of rushing in and giving them what you would want, which is probably not cheerful singing, consider who they are and what they need.
“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.” This principle applies not only to friends but also to enemies, though it is much harder to consider their needs. But in this case we too are parties in the conflict, which only becomes more destructive as it escalates. In extending grace you not only offer peace to them but to yourself, and an opportunity to make amends. There is one thing we naturally want that are enemies also need, and that is their repentance. This too is best achieved by kindness, which heaps the burning coals of conviction like nothing else can.