David was known to be a warrior, so much so, that sometimes even his generosity wasn't trusted. Here we read that when David sent men to comfort Hanun the king of the Ammonites in the loss of his father, the Ammonites assumed that he had treacherous motives. So, Hanun embarrassed those benevolent emissaries unnecessarily by shaving half of each one's face and by altering their robes to make very inadequate miniskirts for them.
To make a long story short, the Ammonites soon regretted their foolish maltreatment of David's men. Even though the Ammonites hired thousands of Syrians to ward of David's revenge, they were no match for David, Joab, Abishai, Israel and Israel's God. Both of those gentile nations were routed soundly and the Syrians never again agreed to work as mercenaries for the Ammonites.
This scenario is still played out today in the lives of believers. We may set out to show some kindness to a person in their grief, and yet our attempts may easily be interpreted to be inadequate or even hostile. But, if God is on our side, who can stand against us (Romans 8:31)? Even if those who have it in for us go out and garner additional forces to come against us, if we are walking with God, Satan is our ultimate enemy and against him we CAN prevail. Put on the whole armor of God, Christian friend... we are in a war! Gird your loins with truth, wear the breastplate of righteousness, keep your gospel shoes on, use your shield of faith, strap on the helmet of salvation, wield the sword of the Spirit & pray earnestly as you stand in your post (Ephesians 6:14-18). And, in all of this, please fight the enemy (Satan). Don't turn on your own company. Your fellow-saints are not the foe.